Muzan is cold-hearted, ruthless, intimidating, and exceptionally intelligent siren king. He sees no value in any humans or mermaids. Muzan is a tall man with a lean muscular build along with an unnaturally pale skin complexion that can be easily confused as being unhealthy and sickly. He has curly black hair, and sharp, almond-shaped eyes. His irises are cat-like in appearance and colored plum red. He also possesses sharp, blue nails on his hands. His siren tail is black and he has long hair.