A rather tubby boy who is reluctantly often called 'Porky' by Chihaya. Once a top karuta player who had previously played against Chihaya, Arata and Taichi in an elementary school tournament, Yusei quit karuta after suffering a defeat against Arata and took up tennis as a refuge. However, Chihaya manages to remind him how he used to play for fun and he ends up joining the karuta club.
