Setsuya Katashiro, also known as Yukiya Katashiro, is a second-year student at Sekirei High School. He actively participates in the school's rugby program, holding positions on both the first and second team rosters. His appearance features long silver hair, frequently tied in a ponytail that sometimes incorporates ribbons, and distinctive grey eyes. He wears Sekirei High's standard uniform: a black coat and slacks accented with red trim, red collar details, white cuffs, and black shoes. As part of the second team, he competed in a practice match against Soran High School's rugby team.