Seishirou Tsugumi is introduced as a transfer student. As a former acquaintance of Chitoge, Seishirou finds Raku unfit to be Chitoge's lover. Seishirou challenges Raku to a duel but is inadvertently outplayed. While trying to revive his opponent, Raku learns that Seishirou is actually a girl despite her masculinity. The day ends with Raku earning a genuine amount of respect and affection from Seishirou.