Webthe main reason why the hashira were confused when they first saw muzan was because, up until that moment, none of them had ever seen him. Muzan is a master. Webas muzan transfers his blood and memories into tanjiro's dying body, he is able to successfully revive him as a demon, deeming him the king of demons he influences. Webas the progenitor of demons, muzan's existence and evil actions are the catalysts for the conflict in the series and the motivations of some of the characters in. Webwhile demon slayers and even demons themselves rightfully fear the demon king, kibutsuji's only fear is once again becoming the weak, dying creature he. Webmuzan believed that humans without strong attachments could not become truly powerful demons and yet douma seems to be the one outlier. Webcontrary to initial belief, muzan kibutsuji's heart stopped several times while he was still in his mother's womb, resulting in a persistent struggle for survival during. Webmuzan kibutsuji is the primary antagonist in demon slayer, whose real powers are yet to be revealed in the anime. However, as the original demon, his powers.