Kou is a handsome young man with fluffy black hair and fairly sharp brown eyes. In middle school, he looked more innocent, but as the years past he changed into looking more mature and serious. He tends to keep more of a straight face and his expressions make it hard for people to read what he's thinking, especially Futaba. Kou doesn't laugh a lot, but when he does, it's very lively and welcoming. It is made aware that he is slowly losing weight and becoming anemic.