Yu Daimonji is the youngest of the three Daimonji Sisters and serves as a police officer. Her standard-issue equipment includes handcuffs and an expandable baton, alongside her police car. She possesses shoulder-length brown hair and blue eyes. Her sisters are nurse Emi Daimonji and geisha Saki Daimonji. The sisters form a tournament alliance, targeting protagonist Aya Iseshima for recruitment. After their collective defeat by Aya, Yu and her sisters are enslaved by Miko Kazuki alongside other tournament losers.