Aki Mizushima
Mizushima is, like Tsubasa, a first year and a member of the band. He is very good at playing the trumpet. In the beginning he tells Tsubasa to leave the club, because he thinks she only joined with light-hearted feelings. He says she would only drag down the club, since other members wouldn't have time to practice when they're tutoring Tsubasa. Later though, he accepts her and believes that she's serious about joining the band. All the time Tsubasa mistakes him for a girl, until Daisuke meets him once and tells her that Mizushima is a guy.