Boku to Kanojo ni Furu Yoru

Sugamu Naito is an ordinary student whose life shifts when he becomes involved in a conflict between magicians known as Makai Juutsushi. He is rescued by a female Makai Juutsushi named Yorumirumi, whose encounter with him triggers the return of some of his forgotten memories. Learning about the dark world for the first time, Naito feels an inner stirring and begins to take part in the battle.