Muzan is the strongest demon of all, he's the creator as he is the King of demons. He's cold-hearted, ruthless, intimidating, and exceptionally intelligent. His physical appearance is like that of a man in his late twenties with an unnaturally pale skin which can be easily confused as being unhealthy and sickly, curly black hair, and sharp almond-shape eyes. His pupils are vertical, like cat eyes, and colored plum red. He also possesses sharp blue nails on his hands.