Tsumugi once participated in student plays, but after a particular incident, he lost confidence in his acting and gave up on his journey to become an actor. But in the end, he got back on his feet and joined the Mankai Company to pursue his dream once again. He is the leader of the Winter Troupe. Although he is a gentle person, he can be timid. He was childhood friends with Tasuku. They were part of the same university theatre circle and decided to strive to become actors together.