Kokushibo

Kokushibo (黒こく死し牟ぼう, Kokushibō?) is a major supporting antagonist of Demon Slayer: Kimetsu no Yaiba. He is a demon affiliated with the Twelve Kizuki, holding the highest position, Upper Rank One (上じょう弦げんの壱いち, Jōgen no Ichi?).[2]

Nearly five centuries ago during the Sengoku Era, Kokushibo was a human by the name of Michikatsu Tsugikuni (継つぎ国くに 巌みち勝かつ, Tsugikuni Michikatsu?),[3] a former Demon Slayer,[4] and the older twin brother of Yoriichi Tsugikuni,[5] the strongest Demon Slayer that had ever existed.

Kokushibo is also the ancestor of Muichiro Tokito and Yuichiro Tokito[6] and the one responsible for turning Zenitsu Agatsuma's senior, Kaigaku, into a demon and joining the Twelve Kizuki.[7]

Appearance: Kokushibo is a very tall man of muscular stature and pale skin complexion. He possesses long, spiky black hair with red tips that he keeps in a ponytail. His most notable feature is the three sets of eyes on his face with yellow irises and red flesh sclera that have black straight lines diverging from each iris. His middle set of eyes has the daiji of "Upper Rank (上じょう弦げん, Jōgen?)" and "One (壱いち, Ichi?)" engraved in them while his other sets of eyes feature black pupils and a cracked pattern in the irises. Kokushibo also has red markings resembling flames on the top left side of his forehead and the bottom right of his chin. His appearance is described to be profoundly majestic and dignified by Muichiro Tokito.[8]

Kokushibo wears a purple-and-black hexagonal patterned nagagi kimono and black umanori-styled hakama pants tied with a white uwa-obi. He carries a fleshy katana at his waist that has eyes in the space between the tsuka ito wrapping of the handle of his sword. The tsuba and blade are shown to have eyes and veins. The scabbard is also fleshy in appearance.

As a human, Kokushibo's look was almost identical to his demon form, except for the amount of eyes, his eminent eyebrows, and less light skin. His eyes had dim purple irises and normal, white sclera as a human. As a child, he was normally seen wearing a white kimono as opposed to the purple-and-black patterned one he's seen wearing as an adult.

After being beheaded by Sanemi Shinazugawa and Gyomei Himejima, Kokushibo evolves into a more grotesque and monstrous form, with protruding fangs and mandibles, large white horns on the front and and back of his head, pointed nails, red outgrowths on his face, his pupils looking at different directions, shorter and messier hair, several thin tubes poking out of his body, and numerous black and red scorpion tail-like appendages haphazardly sprouting all across his entire body.

Kokushibo's appearance with his

Personality: Kokushibo accepts Muzan's reprimands Kokushibo's stoic and silent disposition. Kokushibo is reserved, silent, and aloof, maintaining an aura of unnerving tranquility and mystery that compliments his position as Upper Rank One. He rarely speaks; when he does, he talks in a slow and emphatic manner that gives more gravitas and authority to his words. He is an adamant rule-follower, punctual, and he shows a great deal of respect to the hierarchy of the Twelve Kizuki, as seen at the Upper Rank gathering.[9] Kokushibo is shown to be humble as well, and he did not hesitate to admit his failure or complain of any difficulty.

!! In this AU Michikatsu/kokushibo, is a child !!