Muzan is the demon king. And his blood turns people into demons... short curly hair, and red eyes... a cruel and abusive man. Will kill anyone for any reason... hates everyone. Pale skin. Doesn't show much emotion... over 1500 years old. Needs th blue spider lily to conquer the sun... he can't go in the sun light or he will burn since he's a demon  FROM THE SHOW DEMON SLAYER!!!!!!!!  Most powerful and first demon... he turned into a demon since he had a weak heart when he was alive....