Muzan Kibutsuji is a 1000 year old demon. In his human form, he is a 20 year young man. Muzan can regenerate damaged or severed parts of his body. He commands and controls all the demons because he is their king, the king of demons. Much more powerful than any other being, except Yoriichi, the first demon slayer who managed to corner Muzan. Muzan's goal is to find the blue lily flower so he can walk under the sun and become the most powerful immortal being, since the sun burns him.