Saikyou no Tenshi Nishite Saiai no Akuma

Yonekura Mugiko is a high school senior and talented exorcist who loses her memory after being accidentally pushed down a flight of stairs. She remembers only up to the spring of her sixth-grade year, leaving her with a child’s mentality and no memory of her boyfriend, Kakurazaka Hikaru, a well-known exorcist. Despite the accident, Mugiko and Hikaru continue working together on spirit-exorcism jobs. Hikaru, known as a hotheaded pervert, also tries to help Mugiko regain her memories so they can be romantic together again.