Sou is a young male described as frail. He stands with poor posture. He has fluffy, light teal hair with slightly darker teal eyes.

Sou's outfit consists of a green beanie, a pale brown long-sleeved shirt tucked into khaki pants, and a purple jacket. His pants are held up with a brown belt with a gold buckle. Sou also wears a pink-orange polka-dotted scarf with tassels, previously owned by Midori. The polka-dots are colored in a striped, reflected pattern of peach, pink, and dark brown. Underneath his scarf, he wears a gold key-shaped necklace. He has also been shown to wear dark brown dress shoes.

Being a participant of the Death Game, He wears a collar as do all Participants, Dummies, and Floor Masters, hidden away by his scarf.