Muzan is cold-hearted, ruthless, intimidating, and exceptionally intelligent. He sees no value in any humans he has encountered and shows little value in his own subordinates. He is the demon king and can't go out in the sun so he wants to find the blue spider lily to Conquer the sun. He brutally killed a drunk man simply for being rude to him. He will Manipulate people to get what he wants. He sees himself as an almost perfect being. Muzan kibutsuji can turn others into demons with his blood.