Eri is a young girl in Boku no Hero Academia who possesses the powerful Rewind Quirk, allowing her to reverse a person's body to a previous state. She is initially held captive and abused by the villain Overhaul and the Yakuza organization Shie Hassaikai, making her one of the series' most tragic and protected characters. After being rescued by the heroes, Eri becomes an important symbol of hope, recovery, and the consequences of Quirk misuse. She also plays a key role in helping illustrate the emotional stakes of the hero world.