a page just to collect headcanons for @tsukkiakarii! all of these posts were originally on the blog, but this serves as a back up + a way to access the info more easily since my koku is canon divergent!please feel free to ask if there's any questions!carrd 🌕 blog

Main Verse Plot

much like rabbit, i thought it’d be good to make a summary of our plot for our main verses!note that they’ve been involved in some way for quite some time–kokushibō was tasked by muzan to keep an eye on and tend to the newly turned dōma, and while she initially followed these orders in a strictly business manner, dōma's gratefulness shown to her resulted in kokushibo continuing to look after and protect him. thusly, each always had the other, from the night dōma became a demon. their friends-with-benefits stage began when dōma became upper six, whilst their more exclusive relationship following were a natural progression over time--leading to their marriage and family: they’ve been involved with each other for an extended length of timeinitially, kokushibō viewed their interactions in that more distant way: she initially sat by his side as he turned, remaining next to him and only leaving to return with food. she likewise helped him to adjust to being a demon--the gratefulness dōma showed her resulted in kokushibō continuing to protect him and look after him, even eventually visiting the temple to see him.she didn’t fully intend to bind dōma to her and keep him wrapped around her finger, but as her affection and fondness for him grew, it became a much more intended thingthey also didn’t really intend to feel such love, but it were a gradual thing that kokushibō didn’t fully notice until they had already fallen for him, an epiphany when he protected her from the sun one dayit was after this that kokushibō began truly showing dōma her acceptance and showing that love, in the realization that she could, and without him feeling emotions, he wouldn’t care anyway–and it was this acceptance that continued to grow into further understanding that allowed kokushibō to both fall deeper into that love as dōma never sought to manipulate or use it against them, and to truly just accept and be patient regarding his lack of emotionsshe knew she couldn’t be loved, but he always showed compassion and affection, and that were enough for koku–it was never lost on her that dōma could simply switch to rejecting her or being cruel because he would feel no emotional benefit either way, but he still chose to be kind, and so kokushibō chose to love him anywayto note: kokushibō had a suspicion that dōma’s emotions were there, due to specific moments of his behavior, but she never mentioned this or specifically sought to make him feel–only to accept him, and that desire to have her loved one closedōma allowed kokushibō to feel so much trust within him that she felt comfortable in having that talk, in letting him in and metaphorically letting go of the weight she carried–she went into this with the need to speak, to be heard, and then dōma felt love for herover the course of the events of that night, dōma asked kokushibō to marry him, and kokushibō immediately agreed. neither one planned for a ceremony, but they both wear rings as an officially married coupletheir anniversary is november 22nd--11/22kokushibō likewise understands as dōma’s dissociation goes in and out, and she seeks to soothe and ground him as she tries to help him feel those emotions and feel them healthily, in her want to still care for and show him her own love and affectionand our current place in this plot! kokushibō delivered their twins–truthfully, they were already pregnant when they married, but it were early enough (and kokushibō in a little shock/denial from surprise) that they hadn’t realized it until a couple more weeks afterwardsALSO!!! REMINDER THAT, AKIN TO HOW KOKUSHIBО̄’S PRONOUNS SHIFT BETWEEN HE/SHE/THEY, THEY’RE GENDERFLUID WITH THE ABILITY TO SHIFT AND MAINTAIN THEIR FORM TO REFLECT THIS! THEY’RE NOT CIS, AND THEY’RE NOT A MAN–AND ANY MISGENDERING OR COMPARISON OF TRANS PREGNANCY TO ANYTHING PROBLEMATIC OR TRANSPHOBIC WILL RESULT IN A BLOCK

Their Children

names are listed as first, second, and third twins + oldest & youngest!they are revered by the followers in the temple, all knowing the devotion given to their parents--however, both dōma and koku ensured they were protected from the cult and given healthy childhoods, neither willing to accept any of their children knowing the trauma they knew in their own childhoods. as adults, some remain within the temple with their parents, whilst others leave to walk their own paths--but all always return. whilst all are referred to as lord or lady, they all also possess star based titles, used among the followers in the temple: a reference, too, to their parents being the sun and moon.upon becoming the queen and king consort of demons post-canon, the children can all be referred to as princes and princesses as well.note that none can be expected to be cis, and indeed some degree of fluidity is expected regarding gender/pronouns!------Himiko & Hikari:- Born pre-infinity fortress as daughters and thus the twins present on our blogs now! Their birthday is October 10- Their star titles within the temple are Clever Star and Wise Star respectively. Also nicknamed "The Big Pair", as the eldest twins.- Both twins possess three eyes: Himiko has two on her right and one on the left, whilst Hikari has two on her left and one on the right. All three eyes carry the same rainbows as their father's eyes- Like their younger siblings, they also have Dōma's eyebrows too- Their hair is dark, though they don't have the red their mother has in her hair: as a result, it's more reminiscent of Michikatsu's- Their skin is pale and carry the same star-like markings that Kokushibō has, a trait all of her children possess- When fully grown, their height is on par with Kokushibō's and thus about 6'5". Likewise, their features seem much like their mother's
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Himiko tends to be quiet and thoughtful, whilst Hikari were more mischievous as a child; as the years go by, Hikari grows to become quite level-headed and Himiko becomes bolder, coming out of her shell
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Their demonic arts draw upon the concepts of life and death, respectively: Himiko gains a healing, nurturing blood via her mother, whilst Hikari gains poisonous blood via her father and the wisteria in his bodyKazuya & Kosuke:- The first children born post-infinity fortress are their twin sons, their birthday falling on July 05- Their star titles are Bright Star & Radiant Star, respectively. As children that always remain at the temple, they gain additional titles as well based upon the roles they take in adulthood: aiding in funerals, keeping records of births, and thus becoming Keeper of the Heavens and Keeper of the Dead. They also become known as "The Little Pair", as the younger identical twins.- Unlike their older siblings, the sons have hair as golden as Dōma with eyes as golden as Kokushibō, minus the red sclera their mother has--as a result, they're often compared to the sun- Each possess four eyes, and again asymmetrical: Kazuya has three on the right and one on his left, whilst Kosuke has the inverse with three on his left and one on the right- Like their older sisters, both sons have Dōma's brows and Kokushibō's skin- Upon reaching adulthood, their height is more akin to Dōma's: as a result, they similarly tower over their mother at about 6'9". Their features, similarly, are closer to Dōma's as well
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Both sons are energetic and rambunctious as children, with a knack for getting into things; as adults they can be goofy and playful, but become serious when needed--much like Dōma himself
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Their demonic arts draw upon planets, and specifically Jupiter and Pluto. Drawing from these associations, Kazuya possesses the ability to manipulate air, whilst Kosuke can manipulate the earthManami & Megumi:- The youngest set of twins, they are one last son and one last daughter post-infinity fortress, born August 14- Their star titles are Glowing Star & Sparkling Star. Not to be excluded, the last twins become known as "The Smallest Pair".- Much to their parent's surprise, their youngest children actually have the eyes of Michikatsu: violet purple- Each possess five eyes, but are the first to be symmetrical: each have two on each side, and the fifth upon their chin- Once more, Kokushibō's children have her dark hair--however, similar to her own red, the twins have streaks of blonde reminiscent of Dōma's hair as well- They both, like their elders, possess Dōma's eyebrows and Kokushibō's distinct skin- Manami's features seem to resemble Kokushibō's a bit more, whilst Megumi seems to favor Dōma. Likewise, Manami grows to Kokushibō's height, whilst Megumi continues growing to Dōma's
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Of the children, it is they who take after their mother's personality the most: they both have a tendency towards introversion and quiet, generally noted as being very calm children. As adults, they remain reserved--though are rather passionate about that which they care for
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Their demonic powers are more elemental: they pull from light and dark - photokinsesis (light manipulation) and umbrakinesis (darkness manipulation) respectively

Identity and Presentation

in all verses, she’s amab and trans–these are my three most commonly used verses but it carries to verses not here as well: the only thing that can differ is how they present and how comfortable they are–i.e., during her time as a human (prelude to main), she did still experience dysphoria around how she were perceived and the ways she presented herself in the sense of believing she couldn’t be herself, but only what others deemed she must be (aka the biggest cause of her dysphoria is being misgendered)main verse - shape shifting means kokushibō is able to change form to be more comfortable, choosing how she presents herself freely; current plot means she will be femme though, dictated by the fact she’s pregnant. following this, while she would again be able to change form freely, she’ll often favor being in femme forms regardless of how she presentsmodern verse - amab, but has had bottom surgery (though not top). will adjust how they present via clothing/makeup/etc., and is very happy in her body!!pillar verse - amab, will often be more self-conscious or withdrawn when it comes to their body, depending upon how their gender-fluidity is nudging them to feel. they’re working on it uwu

Weapons

for much of her existence, kokushibō solely used kyokokukamusari as primary weapon if she used one--crafted from her own flesh in imitation of the lilac blade she had once wielded as a member of the corps, though formed of twisted flesh like the bark of an old tree and lined with eyes entirely capable of sight. in many ways an extension of herself--due to its status as not only being made of her flesh but also so much of herself placed within it via her biokinesis, kyokokukamusai were not capable of full sentience or complex thought and yet still possessed nerve and instinct: refusing to be drawn if kokushibō didn’t wish to, twisting and lunging if another were to attempt wielding, rattling in its sheath if kokushibō became too distressedin time, dōma also teaches her tessenjutsu with fans kokushibō crafts herself--two in a black metal that appears similar to black zirconium or black titanium, expanded spokes on the spines and decorated with a pattern of the moon and falling leaves. lacking the ice he possesses, she uses hers in junction with her umbrakinesis to instead fine tune her manipulation of shadows and darkness, taking the form of inky black that covers the senses. named by dōma, the fans are yorunojoō and kuīnobuyoru--both named for the flower titled the queen of the night.further, in her blog canon survival verse, kyokokukamusari is no longer the only blade at her disposalafter the war against muzan and her ascension as queen of demons, along with dōma no longer remaining able to battle, she crafts two new blades: the closing of an old chapter and the opening of a new. named ryōhasureinutsusu and kanayōtoakiutsusu, these twin blades are more akin to style of tibetan ral gri than katana--just as goutouge drew so much from tibetan buddism regarding the cult. likewise, her fighting style in dual wielding is very reminiscent of how dōma once wielded twin fans for she learned much from him and likewise, her dual wielding is in many ways a way to carry on his legacy--including both blades being named for him.like many ral gri, the blades are decorated in lotus patterns just like dōma’s fans--rather than remaining a grotesques show of biokinesis and strength, they’re instead polished and beautiful. likewise, the pommels of both are in style of lotus, especially important because combined with both being made of her flesh, she can combine them together in a style very similar to a dual-bladed naginata: the traditional weapon of women of the samurai class.when in use, a visual example of her fighting style would be the boss battle against alva in gow: ragnarok--she attaches and separates them smoothly based upon need, and combined with her own agility and prowess, remains a dangerous weapon(s).being made of her flesh still, if either is broken it will regenerate just as kokushibō’s body herself will in mere moments, the only evidence the fact that this also means the weapons will bleed her own purple-black blood (a headcanon graciously given by rabbit!) in the precious seconds before the damage is undone. granted, just like kyokokukamusari, ryōhasureinutsusu and kanayōtoakiutsusu will also absorb any blood or gore upon them whether its kokushibō’s own or her enemy’s--made from her own flesh, any of the weapons absorbing blood gives it to kokushibō as well.

Demonic Arts + Expansion

basically, i agree with the idea that kokushibō, esp as upper one, the second strongest and second oldest demon with the highest amount of muzan’s blood, rly should’ve had more than just moon breathing 2: electric boogaloogeneral note that affects each point below is that his arts greatly reflect the night and the moon, and likewise, his powers are affected by them: he’s able, for example, to make greater use of his umbrakinesis during a new moon and his hydrokinesis during a full moon. likewise, akin to moon lunacy, it’s common for animals to become more aggressive in his vicinity as well.when first turned into a demon, it were her biokinesis that were her innate and original demonic art–over the centuries of devouring and becoming stronger, it developed further and she also gained access to the following demonic arts as well.before getting into them, it's to note as well: her voice (and the fact that her natural voice as a demon is multiple voices speaking at once) is related to her biokinesis and shapeshifting. not only were her shapeshifting a show of her inability to truly be Enough, but her lack of voice further symbolized her lack of autonomy for her own fate.BIOKINESIS: the ability to change his physical form. in most cases, this involves still appearing humanoid–some of it is very subtle, in hiding his claws or shortening his fangs. some is more overt and obvious, like when kokushibō changes how he presents himself based on his genderfluidity (and thus may appear more masc, more femme, or neither). she’s even capable of shifting features like hair color–night-black is most common due to being her natural color in humanity, but she may even employ bone-white. it’s described more fully in (this post) ¹ , but she’s also able to more fully shift her form completely into non-human beings as well. even when not in a human form, she still has access to her other demonic arts. on that note, like how he creates kyokokukamusari, kokushibō can craft smaller blades with eyes that he similarly gets feedback and sight from still. more on the blades and the infected form of possession they can do will be found (here) ².¹ it was already established they can shift form to either a giant saber-toothed feline that’s larger than a grown man or separating into six more housecat sized cats, but to turn this into even fuller and more proper biokinesis, this isn’t the only form they’re able to shift to!they have more of an aptitude for nocturnal animals–spiders, bats, snakes, sea serpents, cephalopods, and moths–but each is equally giant. shifting is often based upon practicality and whether they just feel like it, such as: covering distances, need to climb/fly somewhere high, a need to reach depths in water that hydrokinesis alone won’t allow her to reach, as well as purposes like blending in or sneaking bylikewise, she’s not obligated to fully shift; she could forget to switch away from cat ears, or have a cat’s tail. she could keep her upper body humanoid but have the lower half of a spider or snake. she may borrow the wings of a bat or moth. she’d still possibly forget antennae or ears. akin to canon when her biokinesis went haywire after overcoming decapitation and regenerating her head, she may separately craft the spider’s legs from her back/originating at her spine.when she does fully shift, her forms are all quite large, larger than grown men, though there’s some variation between them still. they also all carry her customary colors of blacks and purples and reds, with six eyes. however, she still carries the ability to separate into up to six smaller versions, one eye to each. some forms, such as her feline one, starts with six tails which are divided each time she separates.if pushed far enough, she does possess a more monstrous form--akin to her biokinesis going haywire in canon and yet a more refined and controlled version, effectively all of her forms all at once. A reference (with nudity) is here; note this form possesses six tails as well as the other details shown here.much like death and the moon, she’s quite simply a force of nature, but rather than muzan’s comparison of himself to storms and natural disasters, she’s flesh and bone and often too-willing to maim in her hunger² much like how goldnail effectively infected an empty suit of armor to become blight and needed to be removed from the armor to actually deal damage, kokushibō is able to use their biokinesis and ability to create separate swords (akin to kyokokukamusari) to similarly “infect” inanimate objects and cause them to move akin to a puppet or automaton, branching from the detail that these swords all remain as pieces of kokushibō and possess a form of sentience.if one were to try picking up kyokokukamusari, besides kokushibō themselves or even dōma, the blade will lunge and twist to break the grip–and even initially did this towards dōma as well, until kokushibō grew more comfortable around him as they had grown closer. it’s not full of conscious thought or the rationale for complex or informed decisions, but instead functions in a form of running on nerves and instinct. if kokushibō is distressed enough, the blade may still respond to that itself and rattle in its sheathe, or if kokushibō doesn’t wish to draw the blade, it may refuse to be drawn outright.and this sense of infecting or possessing branches from this.when used by kokushibō, it’s often in the form of taking suits of armor–the only way to actually defeat them is to remove the blades possessing them, but they otherwise are hollow and inanimate enemies. unless the blade is broken too much to regenerate, it can just re-possess the armor.however, there are taxing things in this as well: each time kokushibō possesses something, she must share her own power with it, and thus she herself will become weaker until the other possessions end and her power returns to her. likewise, it’s a process to craft a blade suitable–while blades protruding from her own body (such as what was seen in canon) take only a moment, actually separating them and turning them into a fully formed and sentient sword takes more time, more energy, and a bit of blood and pain–even crafting her own sword at her hip is a similar process, if it too became too damaged to regenerate.her limit in this possession is six–incidentally, the number of her subordinates that had been killed by demons. due to the splitting of power, however, she rarely crafts more than just two.a related form is in what may outwardly appear as re-animating corpses, though it’s relatively less taxing on her. in this case, she effectively just takes control of whatever is left, not unlike turning the gears of an automaton to make it move, rather than fully creating its mechanisms from scratch. this can be any corpse as well, whether human or animal–and regardless of state of decay. however, while fresher corpses may initially trick someone, there is an inherent sense of wrongness–they are unable to move in a natural way, instead moving in ways that are jerking or rusted, if not entirely unnatural. anything already decayed similarly isn’t returned, and so an older corpse she has animated may still be skeletal or covered in rot and moss despite it moving. due to the fact they’re long dead, none of them are able to feel pain–and indeed are nothing more than puppets controlled from within to move with a steady momentum until broken down. if in need of one, she may simply hunt and instead of completely devouring flesh and bone, simply eating her fill and leaving enough to animate.in related note, when she devours someone she is able to use their voice as her own in a form of mimicry: something regularly used to distress, lure, disarm. it can be used to lure in more victims, those searching for a lost companion only to be lured by familiar voice into spider's web or to cause fear in an opponent during battle.UMBRAKINESIS: mostly takes the form of stealing light; lanterns will dim and candles extinguish, shadows lengthening until the area is plunged into something as dark as a moonless night–however, this has a more limited area of effect. as in, he can’t use this over an entire village or block, instead proving more effective within buildings and other closed spaces. however, even when outdoors, he can still make nearby lights flicker and fail, such as a way to alert another to his presence or signal to them. likewise, he can trick the eye to believe there’s something within the shadows. as dōma teaches her tessenjutsu, this is fine tuned to be higher control of shadows, to conjure and control them in battle instead of merely snuffing out light.HYDROKINESIS: reflecting the moon and the tides, this takes the form of a push and pull. he may push the water to an enemy to throw them beneath it, or pull it towards himself to similarly throw another off balance. if it’s a small enough body of water, he can push it apart to walk across the bottom. if it’s too large, he can simply walk across the surface anyway like the moon reflected upon the waves.ONEIROKINESIS: related most to the illusionary aspect of the moon, inducing dreams and taking others from the waking world to the dream one; in most cases, this is merely observing, though he is capable of inducing or suppressing them. likewise, following the theme of illusions–he’s able to see past them in this way, in a sense of taking away disguises. those capable of lucid dreaming or otherwise realizing they’re within a dream may likewise try escaping from them. due to the theme of either creating or removing illusions, this can likewise fall into the theme of spiritual/emotional healing instead.

The Cult's Followers

kokushibō spends her time at the temple, living there with her husband–beforehand she would come and go. before she and dōma were friends with benefits, it was infrequent and then increasingly regular, and then as they grew closer she would increasingly spend more and more time there, until now wherein she’s viewed as a god within the temple and sees it as her homeinitially, kokushibō was absolutely the image of a cat hiding in a corner–they did not want to be around the worshippers and often took the first out they could find, even if it wasn’t always graceful. they found it all a bit overwhelming and would retreat to the temple’s inner rooms insteadthe first time they properly spent time around the worshippers, it were whilst resting at dōma's side as he tended to them, though they were largely quietit were a more gradual thing as they became more comfortable around them–responding if one addressed them as they rested with dōma, or when happening across them within the temple and pausing to speaknow, her feelings are very much akin to when given a toy phone by a child (so to speak); she’ll play along with them as they act on their devotion towards dōma in showing it towards his spouse as well, offering advice or listening to their troubles, accepting their wishes to aid in her pregnancy, though they always have the mental distance of being less affected in comparison by the constant bombardment of traumasshe has some preference to certain worshippers over others, with the most favored becoming something akin to attendants that she’ll task with things like bringing her sashimi or other things she needs or wants but cannot go out within the day for. likewise, the ones she favors most are given further favor in their deaths: their skulls are kept upon the shelves, and their bones used in divination.initially they didn’t want worship or devotion of the members and pushed back a bit if anyone became too adoring for her tastes, but over time the worshippers began to view her as a god regardless–with dōma as her messenger, she accepted this and will pick her words to encourage this narrative in their mindsbasically kokushibō has become such a fixture around the temple with their marriage and family adding further depth to that, to the point kokushibō will actually consider the worshippers and the stability of the temple whilst hunting and humoring those who approach herdue to the amount kokushibō tends to hunt when eating, they also effectively (mostly inadvertently) push more humans towards the temple based on the fact they don’t freely hunt those who wear the cult’s robes and thus it offers a degree of protection compared to those whom kokushibō deems fair gamedue to her alternative forms, she has likewise encouraged the followers to see them as familiars or signs of her presence watching over them, allowing herself to move freelyshe wears a more human appearance around the worshippers to keep from frightening them, and allows them to refer to her as michikatsu to avoid the questions and curiosity that a name like kokushibō would causeher behavior towards them tends to be surprisingly gentle as a result; she takes actions that encourages their devotion and loyalty, using her sight to help dōma heal them and ensuring their safety and happiness. to those who didn't know a mother figure, she has accepted the role of becoming motherly to them, thus gaining the sort of loyalty between a mother and their children--something she accepts and encourages, esp after having her own children.much of how she has learned to handle them was initially from watching and mirroring dōma--as a result, if she isn't certain how to win someone over, she often mirrors him to fill in the gaps of her own façade.she still absolutely eats them too, oops. this is most often in the form of absorbing them just as dōma had done towards shinobu in the manga–saying that she will keep them safe and protected forever. some see her as the mother figure they never had, some see her as the essence of the divine dark–the night is the closest to creation, and thus it is like a cradle# also the sense of it complimenting their theme’s too # in humanity michikatsu wanted safety and protection and it carried into her demonhood as well # so now when she thinks of what is the best thing to give; it isn’t eternal life but to be safe and held and treasured and protected # also the contrast of dōma being like the sun between them–this life giving thing # whereas kokushibō is the moon and the dark and the essence of the divine dark is that the night is the closest to creation # it’s a cradle # just as she says she’ll cradle them forever

Kotoha and Inosuke

this is going to be a mess because i’m largely rambling but: me thinking abt kokudōma + kotoha polycule, in which (while they were only romantic/sexual with each other), both kokushibō and dōma were queerplatonic towards kotoha + helping to raise inosuke and viewing him as a son...i love the image of upper one looking at this human and her child, seeing the bruises and recalling her own past, and deciding she’ll just take them both under her wing as well, and the (platonic) intimacy as kotoha unknowingly helped to dredge up some of the humanity buried in kokualso: kokushibō viewing this one human differently than the rest--not as a flock or as a potential meal or someone to turn, but someone to care for and protect until she lived out her natural daysuntil, of course, kotoha discovered the truth; kokushibō still offered to go after her and held back when dōma refused, but the way she offered not just to protect dōma but also out of the affection for kotoha as well, and seeing her as family. so she mourned at the gates of the temple, until dōma returned and she set aside those feelings to be strong for him insteadand the next night, she searched for the baby she thought of as a sonshe still calls it a betrayal, she still feels the sting of kotoha’s words as she ran, she’s still just as guilty even if she didn’t kill and devour one she also loved--she just tries to keep them bottled and out of the way lest she cause dōma discomfort with them, for she knows well how he feelsme also thinking of how refusing to let kokushibō go after her could have been a mercy of dōma's too--since kokushibō Felt Everything and thus could have had more distressing effects afterwards otherwiseher experiences in losing kotoha and inosuke also add into kokushibō’s distrust of humans due to her feelings of betrayal, and that colors how kokushibō views every human afterwards: either a potential addition to the faith, a potential meal, or a threat to remove

Gyutaro and Daki

kokushibō met daki and gyutaro the first night dōma brought them to the temple--at that point, they had already been involved with each other for at least a century (ever since dōma became a demon, really) and so not only were the two upper ranks rather close, but koku had already made her home within the temple and given a place within itwhen koku and dōma first met, it was koku being tasked to look after him and ensure he flourished as a demon rather than withering away, and when dōma brought the siblings, she instinctively took a very similar path: taking daki and gyutaro under her wing and teaching them to survive, to thrive, to grow stronger--teaching everything she thought they should know as if they were her ownof course, she never says these words aloud--not unless either were to show any reciprocation. koku is content as is, though it doesn't stop her from occasionally spoiling them herselfand their loss is not met without grief#obvs!!! #there can be some smol diffs based on any muns that write them!! #i.e. i have plots where koku takes a much more actively motherly role for example #but i tried to keep this one v generic--

The Kamados + Blue Spider Lily

anyway this has to do with why i hc that the kamados were descended from yoriichi, and thus kokushibō’s nephews/nieces, since i based it on half a dozen canon details and it’s an essay to re-write each time,,,, this is also largely pasted from one such essay so it’s very unpolished compared to my usual posts and half of it ended up in the tags anyway oopsbut!! it actually did start with tanjiro’s resemblance to yoriichi (and also tanjuro, his father’s, resemblance too), because all of them have the same hair color, the same eye colors, and the same type of marks on their foreheads–and it’s noted that those who did successfully learn sun breathing tended to have such marksnow, to sun breathing–it was implied that anyone could learn any breath, but also that hereditary things could help users too (for example, tanjiro was a v good water breather, but it never quite fit, not like sun breathing did). i.e. someone related to a breath of flames user would have an easier time learning flame breathing compared to someone else. it was also similarly implied that sun breathing itself is rather difficult to properly learn and execute–kokushibō, for example, can recognize each movement, but michikatsu never had the ability to actually perform it–and that’s what created the branching breaths in the first place. if so few could learn sun breathing, one became six, then those six branched furtherand!!! we know muichiro is canonly kokushibō’s descendant–in the swordsmith village, when he regains his memories, muichiro specifically draws parallels between his father and tanjiro (same eyes/same color eyes, same hair color, similar expressions). but the most logical way tanjiro could have a family resemblance in such a way goes back to yoriichi’s genes being present as both branched from the twin’s parents, thus allowing yoriichi’s traits to show in the canonly known branch as well as his own branchit was also shown that something about the tsugikuni blood reacts oddly to demon blood, such as how kokushibō was very resistant to it and took three days to actually turn (and in my blog, exists with the curse already fractured if not fully broken). meanwhile, the kamado sibs: tanjiro conquers the sun in 0.2 seconds and nezuko is also a highly unusual demon in several ways–like the idea that that tsugikuni blood helped them!also also!!!in canon, tanjiro recalled the blue spider lily in the match with rui because he had seen it as a child, because gotouge talked about in some taisho secrets that kie (their mother) had taken him to see where they were blooming–but they also canonly bloom on the grave of yoriichi’s wife, utain another part gotouge talked abt how the home the kamado ancestors were in was actually yoriichi’s and uta’s, and that yoriichi had met them because after being exiled, he was returning home when he saved sumiyoshi.thus another hc i have is that kokushibō knew abt the kamados, but out of her own guilt/regret, especially after yoriichi’s death and her curse being fractured, she actually opted to protect them rather than attack–because i found it odd how the kamados had no knowledge of demons until the beginning of the series, when it was shown to actually be a very dangerous place with skies overcast enough that demons could be about in the day (such as nezuko being moved outside in the day)and she protected them until the only demon she couldn’t protect them from came–muzani hc that she never tried fully breaking the curse not only because. where else would upper one go, but also: in a sense of keeping friends close and enemies closer, she could know his movements and account for them if she were there. but then either muzan attacked whilst kokushibō was away, or kokushibō was forced to retreat before he caught her and punished her too# the last part also leads to kokushibō actually knowing of the blue spider lily’s and their location # and similarly having opted to not actually share that information with muzan # the way she focuses on slayers but ignores the flower isn’t an accident and is actually v deliberate # i’ve talked before privately abt her even going so far as hiding them in her dream world via demonic art # so that no one but she herself (or those she chooses to take with her) actually know and can reach them # which i have no doubt plays also into how important family actually has always been to michikatsu/kokushibō # a sort of spite towards the one that again and again took her family from her # and adds even more into why in main verse kokushibō is so incredibly determined to keep her family safe # a refusal to make the same mistake again

Her Father's Death

at the root of it all, it were by and large makiami’s treatment of his family that drove the wedge between the twins, and caused a great deal of michikatsu’s and thus kokushibō’s insecurities and lack of self-worth--for the trauma his abuse left always existed as a cloud above her and was something that could never be escapedwe saw his temper and violence in the manga as kokushibō recalled her childhood, but it’s highly doubtful that makiami suddenly changed after the death of akeno and yoriichi’s disappearance, instead continuing to his death through his failing health, even considered grown and yet michikatsu still bore bruises, swollen face, busted lipit were assumed he fell ill. it were assumed stress simply grew too great for one so terribly superstitiousit were assumed michikatsu’s apathetic response was uncaring, rather than hiding their reliefin truth--the japanese wisteria, a type of yew, is one of the most highly toxic woody plants on the planet, not just to demons but to humans as well, the toxin taxine causing tremors, difficulty breathing, and death caused by heart failureit were considered dishonorable for a samurai to use poison, but years of humiliation, of pain, of being shoved into the dirt eventually pushed michikatsu to show just what dishonorable actually meant#also the way that she used wisteria to do it #the plant saved her from her father's abuse #and then a member of the corps it protected against demons #and then centuries later #wisteria being both what kokushibō helps dōma to stop and the type of poison she eventually saves him fromto add to this also, the fact she becomes immune to wisteria herself--much like marechi, it isn't completely without effects upon her, but rather than something lethal its something she can force herself to endure and grow to tolerate. she doesn't like it, she isn't fond of it, but she can survive alongside it. it can cause headaches, or make her eyes/nose burn, but its effects are far more akin to allergies than something capable of harming her--much like her immunity to marechi

Divination

divination was so popular by the edo period that, to translate a first hand account into layman’s terms–there was a diviner every five feet, but it was on its way to being so popular in sengoku when michikatsu were still a human and nobles would regularly seek out diviners regarding whether a venture would be successful or unsuccessful, etc.–initially divination was more exclusive to the imperial court before spreading further to the rest of the populace, much of it originally from the mainland such as china and koreabasically, as a human, michi–especially in her time among her subordinates and on campaigns, was very familiar with it first from observation of sitting behind her father and watching, then sitting shoulder to shoulder as fellow soldiers read as well, the later being where she actually grew interested and learned first in curiosity and then intriguethe forms she still takes part in are mainly categorized as casting lots or scrying: tossing and reading bones, reading the cracks in bones, looking into still water, reading the shapes and movement of shadows, or interpreting the signs in dreamssomething she will do for the followers if she deems it necessary is a form also repeatedly shown in japanese (shinto) mythos called ukei–giving the follower an item (often one of her night flowers in the gardens she tends to) and the answer to their question, such as positive/negative or successful/unsuccessful, lies in whether it withers in a certain timeframealso–because astronomy and calendar making became tied into diviners during the earlier heian period, this is where michikatsu’s interest and knowledge in astronomy actually grew as well, beyond merely using the stars to guide as a compass# my fav thing also # is the way that her forms of divination as a human foreshadowed her demonic arts as a demon # biokinesis in her casting and reading bones # hydrokinesis and umbrakinesis in her scrying via water and shadows # and oneirokinesis via dream interpretation # also her using ukei near exclusively for the followers because of how it’s tied to amaterasu # and effectively using it to solidify her own godhood in their minds/the lore of the temple # because she’s basically taking a known method already associated with a prominent god and then slightly adjusting it to be her own in a way

Sleep + Eating

kokushibō sleeps a fair bit, too–i hc that demons don’t need sleep in the same way humans do, and kokushibō could go ages without sleeping at all–it’s not a daily thing, but rather a “years could pass before they actually felt the specific tiredness of the need to sleep”.except kokushibō is a.) the second-oldest/strongest demon in the series and b.) a giant cat usually in human skinakin to nezuko, and related to the fact they’re a tsugikuni, they’ll regularly sleep to satisfy hunger when they don’t actually feel inclined to go hunting–largely due to the amount they need to consume to actually feel full and the logistics of managing it. sometimes, sleeping off the hunger pangs is just easiersimilarly/akin–if kokushibō is weakened or injured in some way that isn’t regenerating properly (such as when receiving their scar from sun-breathing), sleep becomes a solution to try allowing their body to still heal fasterbut even beyond that, they’ll just allow themselves to cat nap or doze off when content enough–not a deep sleep, but still resting. as a treat. if really content, they’ll even purr in these momentsbut that adds up to meaning kokushibō generally doesn’t give themselves the opportunity to feel sleepy, and instead is more akin to “okay, i’m going to bed” and then just doing itif they went long enough though…….sleepiness for kokushibō is a very lethargic and languid thing, soft yawns and moving to be more comfortable bit by bitthey are a light sleeper in general still, and someone staring for too long is enough to make them return to something more alertplaying on the fact she’s a tsugikuni and thus uniquely resistant to demonic blood (such as how even in main verse, the curse is fractured), she isn’t fully obligated to hunt humans–akin to nezuko, kokushibō is able to sleep off hunger instead of eating, which partly leads to how they have a tendency of sleeping more than other demons maybut, also–they’re able to eat things besides human as well, though this isn’t perfect. i.e., they still can’t properly eat typical human food, but they can still take out a whole raw steak without trouble. plainly put: as long as it’s raw flesh or blood, even if of an animal instead, kokushibō can devour it where other demons wouldn’t be ablegranted, they’ll also (canonly) devour demons too, so basically if it moves it isn’t entirely safe from being lunch depending upon nothing more than kokushibō’s whims and mood at the time

Drinking + Smoking

while as a human, Michikatsu regularly drank sake--most often for social reasons, as its use was so ingrained in the culture of the day. it was something they partook in mainly with subordinates, before battles and just enjoying company, until they were all killed. afterwards, when a member of the corps instead, they still would periodically drink: never to get drunk per say, but instead a way to relax or (as their misery turned ever more severe), a way to quiet their feelings and numb themselves.as a demon, she initially continued to periodically drink for the same reason: desperate attempts to quiet her mind and numb her feelings. now, however, as a result of her relationship with dōma, she instead only drinks occasionally and as a social act once more--not using it to cope, but instead nothing more than relaxing.generally, she defaults to still using o-choko, but is still fond of sakazuki even if they’re not the most practical vessels. though she’ll accept certain wines, sake is still her preference.tobacco came to japan after she had become a demon--roughly a century after her birth. however, her reason for eventually partaking in it is the same was why she continued to drink: stress-related.she opts for tobacco, specifically kizami, and still prefers using a kiseru rather than the cigarettes that were increasingly popular by the time the series takes place. tobacco was used more by upper classes and samurai, and kiseru were status symbols--while Japan did have hemp, it’s currently believed it were more for industrial uses such as rope and fabric making, and anything more was relegated to lower classes.much like her drinking, she smokes less than before her relationship, and is often instead done in a social way, such as joining dōma--while she’d accept if he were to offer his own to her, she likewise still has a preference for her kiseru

Piercings

koku has a handful of piercings! besides her earrings, of courseperhaps the second most obvious is a labret piercing at the center of her bottom lip--usually in the form of rings that go over her lip, and generally in silver tonesgoing down, she possesses collar bone piercings--three dermals on each side following the curve of her clavicle, each with a gemstone of alternating amethyst and garneteach finger, too, also possesses a dermal--one each and likewise alternating amethyst and garnet, location close to where a ring would set. on the left ring finger, the piercing is next to her wedding bandnext is potentially slightly nsfw--her last set of piercings are nipple piercings, unlike the rest taking the form of charms. initially, she wore two moon shaped charms--but after her marriage to dōma, she began wearing a sun-shaped charm as well as a moon one still

Reincarnated + Modern AU(s)

there's a great deal of overlap between modern and reincarnated verses, but the main and only real difference is that in her reincarnated au, she possesses those memories and pulls of her past life. in her modern au, unrelated to the canon modern one, she were never a demon at all. in both verses, she is happily married to dōma (@uppertwo).her family consists of her father, mother, and twin–their mother left her husband due to his abusive nature and retained custody of the twins. she still passes of illness when they were relatively young, but they had much more time with her before then and were roughly 18 by that pointpartly out of spite and partly as a final show of separation and independence from her father, whom she still bears strong resemblance to, michikatsu eventually becomes an auditor and compliance analyst–a relatively high-profile job she spent a long time working towardsshe owns her home, but it’s nothing grand or especially large–and she lives there with her spouse, dōma.michikatsu owns a cat named akachan. considering she’s officially diagnosed as ‘baby’ (the name meaning), she’s a rather grouchy cat in general. very particular, kinda territorial in the sense it takes her a while to get accustomed to new people–the fact she’s been caught sleeping with a napping dōma is truly more than anyone but michikatsu themselves can say. solid black and fluffy, though there’s some rusting giving her fur a reddish tinge due to a tendency of hanging out on window sills. she’s an indoor queen of the house.martial arts instructor on the side–she volunteers for it, and regularly teaches classes for those who want to learn, though it’s also just a matter of her enjoying it as wellstill genderfluid!!! and she’s comfortable in it, and has had bottom surgery (though not top). instead she will wear padding and the like to create the appearance of having breastsreminders of her previous life often stir a feeling of malaise and guilt within her, making her skin crawl and leading to her rubbing her arms or rubbing her hands together in discomfort as if she were trying to scrub something offmichikatsu doesn’t truly remember that previous life, and instead she’d describe it more as nightmares she attributes to the events within her life, such as her father’s treatment of his family and herself before separating from himprobably has a mild case of scopophobia, and generally detests horror movies with creatures that possess several eyes/eyes in usual places/general eye fuckery specifically between that and the sense of malaise it causes. the worst, she thinks, is the moments she glances towards a mirror or reflective surface and thinks she sees a face besides her own, one marred by eyesother reminders of her previous life take the form of a sort of deja vu that she can’t quite place, or a familiarity she can’t quite understanda physical give-away of her past life exists in him still having a version of kokushibō's fangs–more pronounced and sharper canines than a typical human, though much smaller than the original demonic ones. likewise, they still take the form of a single set on the bottom and double on top.though there is a large taboo against tattoos even now, michikatsu actually has a large one along her side, stretching from her thigh to her shoulder and moving along her ribs, one that features flowers for much of the length, but is centered with motifs of the moon phases and a skull. this branches from the way that while she still has a birthmark in the form of a slash upon her neck (the cut sun breathing left upon her that night she met yoriichi again), the demon slayer mark wasn’t reflected when she were reborn–and thus, in the sense of something missing, she replaced it with something of her own choosingbeyond her tattoo, she possesses piercings as well, specifically: she has nipple piercings, collarbone piercings, and two in each ear--a standard lobe and another piercing in the cartlidge# i can say a lot more i.e. how she were able to pick the tattoo instead of it being forced upon her # or how it could even be a rebellion against her father # or how rather than being visible it’s also smth she could choose who sees it or knows of it # but uwu

Survival AU

some notes regarding her survival/post-infinity fortress verse!
like rabbit’s, this verse is the blog canon progression of my main verse, adding into the parts of my blog divergent from the series’ canon. this survival verse is basically any time post-series--reincarnation and modern verses both follow her death in canon, the difference being she were only previously a demon in one of the two.basically, between wishing to return to her children, not wishing to defend muzan, and not wishing to fight against the kamado siblings, kokushibō instead abandoned her battle--deserting muzan as she went to dōma instead. however, this only occurs after she conquers beheading, and her biokinesis is going haywire in a desperate attempt to save her.though she doesn’t reach dōma in time to save him from shinobu’s poison, she does save him from kanao and inosuke, keeping him from being beheaded and working desperately to stabilize his condition re: the wisteria poisonshe still tends to and cares for him, helping dōma through the aftermath and supporting him in the ways that she is able to, whilst also working to keep the temple stable and functioning--and, of course, tending to their daughtersshe abandons the battle in the infinity fortress after regenerating her head, but not before dealing mortal wounds to muichiro and genya, along with gyomei gaining the mark that will kill him before the night is done. due to this however, she doesn't leave the fortress unscathed--her biokinesis continues to go haywire for a period of time until she's able to regain control over her body. the wound left by muichiro's red blade results in chronic pain much like the slash across her neck that yoriichi had left centuries before--and gyomei's red flail initially taking her head means she experiences chronic headaches, a dissociation between her head and the rest of her body. it's assumed it is due to her regeneration being so chaotic, but her hair gains and retains sections of white instead of the pure black-red from before the battle.due to the stage at which she left her battle, it's assumed she killed both genya and muichiro unless it's plotted otherwisethere are also multiple different plot points that can be plotted! they have two more sets of twins after the series, first twin boys named kazuya and kosuke, then a boy and a girl named manami and megumi. any time before or after these twins are born can be plotted, as well as during her pregnanciesalso also: with muzan dead and tanjiro as a human, kokushibō is the strongest demon remaining alive, thus becoming the new queen of demons--as a sort of truce, kokushibō doesn't seek to create new demons nor follow in muzan's steps, on the condition that her family and the temple will be left in peace. that said, she hasn't Not given demonhood to the very rare and select few deemed worthyremaining demons and those she turns afterwards to "save" them are treated in much the same way as she treats the followers within the temple: in a way reminiscent of a mother, taking advantage of instinct to garner loyalty and allowing them to feel as if they're loved and will be taken care of, however true that is or not. likewise, kokushibō still devours demons, but instead of a punishment like muzan it's more often in the form of treating it as an high honor: those she devours or absorbs will be protected by her forever, even moreso in this verse as she keeps their consciousness (not unlike what was shown with muzan and tamayo).in a way, after her reigning as queen of demons, such beings instead become another branch of the eternal paradise cult--likewise, those she commands are barred from harming the temple or its followers, lest they do know punishment.

Pillar AU

she joined the slayers when her family and subordinates were killed by demons, along with gaining the knowledge that her twin had become one as well
however, this isn’t so much a sense of i have to find a cure as it is actually i have to stop himshe’s still deeply affected by this and struggles with the trauma and processing her emotionsgenerally speaking, while i keep some regular canon theme’s, the tsugikuni twins also basically fill the niche’s of each other–not perfect reversals, but parallel rather than oppositethe moon pillar that practices moon breathing, a breath she created–she also spends quite a bit of time training other slayers and helping them either learn or develop breaths as wellamong the pillars, michikatsu tends to have more of a loner type of personality, keeping to herself (unless it’s dōma) unless she’s approached by another and often playing the role of a sort of helicoptering guardian–trying to look after the rest, and ensure they don’t get into too much troubleor, at least, too much trouble they can’t get out of. some ppl gotta learn the hard wayshe’s more approachable than her canon time in the corps, at least. in battles with another, she’s prone to protecting them as well as defeating the demon at hand, leading to divided attention and reckless decisions made in the moment before she has time to properly think about itthe butterfly estate-equivalent is pretty accustomed to seeing her needing to be bandaged up. again. and also her trying to just up and leave anywaystill genderfluid!!! and like in her modern verse, she can easily accept any pronouns another character refers to her by whether that’s he/him or she/her or they/them. she isn't currently out however, not fully, and so little still is shown in how she presents herself just yetfor pillar (and her human verses wherein she’s a slayer), her crow is tsuki (’moon’). perhaps a bit of panic to think of a name is how the moon pillar’s crow were named ‘moon’, but it were never changed and so the name stuck. the crow can be a little done with michikatsu at times and judges certain choices, but is similarly a bottomless pit of an appetite so they get along well enough by virtue of bribing with foodin time, she marries dōma (@uppertwo)--affection that had lingered for so long, though one she initially attempted to push aside lest she break his heart when her mark inevitably causes her demise

Trinity Blood AU

this is an au for koku in a trinity blood verse, complete with a bit of world building added in--i've made effort to ensure it fits in with the rest of tb lore bUT still an au lolthe other thing to note is that as with all other verses, koku is with bunny's doma in this verse, and all references to dōma are specifically for @uppertwo!in trinity blood, humanity created four humans to lead the red mars project--a colonization program aimed at addressing earth's overpopulation and resource scarcity by attempting to turn mars into a viable colonyhowever, upon mars is found the ark--an alien ship crashlanded there eons beforehand, containing the remains of two types of beings, one of which found to contain the kudlak and the other the crusnik. in short, its discovered any human can house the kudlak, but only those four created humans can survive the crusnik. in short time, these bascillus and nanomachines, along with the technology of the ark, leads to outbreak of war on earth as various nations fight over just who it belongs to, leading to civil war upon mars and armageddon on earth.but lets back up a bit.originally, there were four created humans sent to mars, four to lead the red mars project, but two more were created on earth. originally intended for a bright future, originally intended to lead an expansion of the colony to allow more humans to escape to mars and create a fully fledged civilization upon its red soil, their role quickly turned into something akin to delegates between earth and mars as tensions rose between the two.and then those who went to mars returned to earth, bringing with them the kudlak and crusnik. the kudlak, ill-suited to a planet closer to the sun, began to have ill-effects upon those carrying it, effects that likened the returners to vampires of old, becoming the methuselah who must avoid the sun and silver, long-lived with a need to consume blood.due to a fatal accident, it is cain that becomes crusnik 01. abel, and then seth follow as 02 and 03. finally, lilith's hand is forced as 04.but the other two remained on earth, and as the war rages between earthlings and those returning from mars, take a stand of their own to protect one another in becoming 05 and 06--dōma leading the way, and michikatsu following shortly behind.by the time centuries pass, new boundaries drawn and the dark ages over, they've created a realm of their own east of the empire's lands, a realm far removed from the vatican's reach and thus a very neutral ground, drawing no allegiance in the cold war between the two and yet welcoming those who seek them out whether human or methuselah. like the empire's empress, they have reigned for as long as anyone is able to recall, true nature hidden and instead the image of a beacon of safety and stability in a troubled era.as crusniks, both dōma and kokushibō are able to appear as humans unless their nanomachines are active, in which the most distinct difference is the wings that sprout from their backs and eyes turned reddened. dōma's wings are akin to a butterfly, cast in colors of red and black and white, whilst kokushibō's are more akin to a bat or the legends of dragons, scales and leather and claws in a deep purple.like the other four, their weapons are created from their own blood, with dōma wielding a pair of folding fans and dominion over ice and sub-freezing temperatures, seemingly drawn from the absolute zero of space. kokushibō's, on the other hand, takes the form of katana, her powers more akin to gravikinesis--she a center of gravity herself, able to create voids and hot spots of force, bending the light around herself.like abel and seth, neither have fully fused with the crusnik nanomachines.

Names

TSUGIKUNI
father: makiami
mother: akenoMICHIKATSU
as human
wife: sakuyahime
first child, son: masahiko
second child, daughter: kasumi
——
as demon
spouse: dōma (uppertwo)
first twins, pre-infinity fortress: himiko (f), hikari (f) {10/09}
second twins, post-infinity fortress: kazuya (m), kosuke (m) {07/05}
third twins, post-infinity fortress: manami (m), megumi (f) {08/14}SUBORDINATES
1. oniniwa
2. iwanari
3. makara
4. azai
5. hattori
6. naganoSENGOKU PILLARS
sun: yoriichi
moon: michikatsu
flame: jin'ichiro
water: nobuyuki
wind: tenshō
stone: bunka
thunder: keiōUBUYASHIKI:
father, killed by koku: minoru
mother, killed by koku: kazue
son, only survivor: shingo

Misc. HC's

the sun is a complicated thing to kokushibō--due to her human life and eye color, the sun were so strongly associated with pain and ache and overwhelming scorching and burning even before becoming a demon that she never felt a desire to see it again--until over the decades and centuries with dōma, she began to feel a pull towards the concept of the sunin a state of confusion one day in the temple, she began to reach out towards the sunlight despite the risks--only for dōma to risk injury to himself to appear behind her and stop her, pulling her back to protect her before she could be harmedit were in that moment that kokushibō understood the concept of the sun as warm, welcoming, even soothing--and that not only had dōma become that sun himself, but that she were in love with himironically, despite her lack of desire to step into the sun's light, she is capable of conquering the sun between her status as a tsugikuni and devouring yoriichi--it's only the fact she has yet to be forced to that she hasn't and is unaware of the potential. in reflection of mythos, the one who never seeks the power is the one who gains it——she has always sought to see the world her twin did, the one she had always been blind to. further, her six eyes mar her face–though the resemblance to twin is still there, unable to be fully erased, it still changes her face so that it’s not quite so alike the only face she can’t forget from her life as a human–this, however, is a very subconscious reason and not one she recognizes (or would easily admit to). even more, it lessens her resemblance to her father.another reason i like thinking of though, has to do with the kimono pattern we see their father wear–a chrysanthemum pattern that resembles eyes, like the moth that wears snake eyes to warn others away, the flower that also symbolizes the autumn and harvest when all things are fading–like one of his chapter sub titles, describing her as culling the living which then returns back to the reaper theme
——
she were 6'3" as a human, but upon becoming a demon her height rose to 6'5"--as well as gaining a much more curvy form and her hair likewise became longer and wilder--now reaching mid-thigh. in many ways, she simply became Bigger upon her transformation even in her base humanoid form
——
we see in canon how marechi only affected kokushibō for roughly one minute, but i like to think that there’s still instances she craves it–but more akin to how someone may crave something sweet, such as chocolate# it doesn’t affect her but she still finds herself craving it # like a treat # actually it rly is like someone having chocolate truffles on hand as an occasional treat of smth nice # but also that craving def has a monthly cycle of being stronger lmao
——
kokushibō’s ears are also somewhat mobile, as in they’ll do things like droop when she’s sad or perk up when she’s happy uwu
——
kokushibō’s least favorite day of the year is the summer solstice, for the longest day is also the shortest night, and she dislikes having to stay inside and be so careful of the sun for that much longerdōma often soothes her via singing to her
——
i tend to hc now that kokushibō has a v warm body temp–much of it due to her demon slayer mark. when she were human, she often felt feverish as a standard (and in human slayer verses, this is still the case)–demonhood took away all of her body’s natural temperature, but the mark were still unaffected besides growing larger, thus not allowing her to feel as cold as she would without it.
——
she's already prone to vocalizations, ranging from purrs, growls, chirrups, and etc. due mostly to how far she leans into her demonic traits rather than humanity--but she also has vocalizations that are so low, humans cannot hear them. so low, they can only feel them; likewise, these vocalizations give the same sort of fear response in humans as a haunted house would--the same sense of foreboding and dread.