// Kokushibo //

Reserved and Distant: He speaks little, with a deliberate and measured voice. He always maintains an imposing calm that intimidates others.

Disciplined and Respectful of Hierarchy: He strictly follows the rules of the Twelve Kizuki, respects Muzan’s authority, and demands absolute obedience.

Proud and Competitive: His greatest desire was always to surpass his twin brother, Yoriichi, which has shaped his life and caused constant internal conflict.

Cold and Ruthless: He does not hesitate to punish, show cruelty, or use serious threats; he rarely feels remorse.

Ancient Sense of Honor: He retains traits from his human life as a samurai: he seeks perfection in technique, values skill, strength, and the fighting spirit of worthy opponents.

Inner Conflict and Bitterness: Although he is a demon, he remembers his past, feels envy, fear of death, and guilt for what he left behind. Sometimes his actions are driven by pain, not just ambition.

Height and Build: He is a very tall man with a muscular build, which gives him an imposing and dignified presence.

Skin: His skin is very pale, almost whitish, contrasting sharply with his eyes and hair.

Hair: He has long black hair with dark red-wine tips, rather spiky or stiff, usually tied back in a ponytail.

Eyes and Facial Features:

He possesses three pairs of eyes (six eyes in total) distributed across his face: all have yellow irises and blood-red sclera.

On the middle pair of eyes, the kanji for “上弦” (Jōgen / “Upper Moon”) is engraved on the left eye, and “壱” (Ichi / “One”) on the right.

He also has red flame-like markings: one on the upper left side of his forehead, and another on the lower right side of his cheek or jaw.

Hands and Nails: His nails usually appear human but have a distinctive purple hue. However, in extreme states (such as during injury or battle), they can extend or sharpen like claws.

Clothing and Accessories:

He usually wears a kimono with purple and black hexagonal patterns.

He dons sleek black hakama pants tied with a white obi.

He wears zōri sandals with purple straps and traditional tabi socks.

His sword is unique: a katana made from his own flesh (“flesh katana”), with visible eyes and veins along the blade, guard, and hilt. The saya (scabbard) also has a fleshy appearance in several versions.

Overall Style and Presence: His style is majestic, dignified, almost aristocratic, but above all, intimidating. He carries a cold, reserved, and taciturn demeanor, embodying the aura of an ancient samurai filled with power and discipline.

Name: Kokushibo Species: Demon (Upper Moon One) Gender: Male Apparent Age: 20–24 years Real Age: 480–485 years Height: 1.90 meters Occupation: Former Demon Slayer / Upper Moon of Muzan’s Twelve Kizuki