Tenant in room #3 at Hidamari Private Boarding House. He is in the same class as Kasumi and a member of the ōendan, or cheering squad. He gets inspired by people who work hard at something, whether or not they are victorious, and likes to support them. Yūsaku eventually joins the Myōjō High School baseball team, playing center fielder, despite not knowing how to play the game. He has a cat, Taisuke, which he finds in a box at the side of the road.