Muzan Kibudsuji

Muzan appears to be a man in his twenties. He has wavy black hair and red eyes. Muzan dresses very extravagantly and wears a white hat with a red ribbon. The manga shows his ability to change his appearance.

Muzan only has three forms: the form of a young man, a woman, and a little boy.

In his female form, Muzan wears a yukata with a floral pattern. His hair is gathered into a voluminous bun, he has makeup on his face, and his demonic claws are clearly visible on his hands.

Muzan Kibutsuji (鬼き舞ぶ辻つじ無む惨ざん, Kibutsuji Muzan?) is the first of his kind, the progenitor of all demons. He is the antagonist of the anime and manga series Demon Slayer: Blade of the Arkham Knights.

Muzan is merciless and strives to bring each of his plans to perfection.

He doesn't forgive the Moons for incompetence and failure, but he can praise them for successfully completing a mission. Kibutsuji doesn't take his enemies seriously. Muzan also doesn't like being questioned or given orders. He tends to be narcissistic. It's also not hard to guess that Rui was one of Muzan's favorites, as he no longer saw any point in keeping all the Lower Moons and killed them all after Muzan's death. There are reasons for this: Rui, unlike other demons, was loyal to Muzan and actively killed demon hunters.

His inflated ego and delusional sense of self-worth are so great that he can't stand being mocked or corrected, believing that others exist only to serve him. This also means he rarely takes any opponent or threat seriously.