Yuusaku is a male student in Ryuujis class and is his best friend. He is the vicepresident of the student council the class representative and captain of the boys softball club at school. Yuusaku wears glasses and has a diligent personality. He thinks he is poor at talking to girls though Ryuuji observes otherwise. During his time as the vicepresident of the student council he eventually falls in love with the student council president Sumire Kanou. A running gag is that he will appear out of nowhere behind Taiga and Ryuuji when they are discussing a plan of attack to get their crushes. Like Minori he has an unusual personality but oftentimes it is an expression of his friendship and appreciation.