High School DxD

A previous all-girls school that recently became coed, Kuoh Academy has a secret. Unbeknownst to regular people, students include angels, fallen angels, and devils. Issei Hyodo, a lecherous second-year human student who leads a tranquil existence, is one of these students. After a routine school day, Yuma Amano unexpectedly asks Issei out on a date. After their date, Yuuma takes Issei to a nearby park where she makes the shocking request that he die for her. She attempts to murder him after revealing herself to be Raynare, a fallen angel. He is revived by Kuoh Academy third-year student Rias Gremory using her summoning card. The following morning, Issei awakens and believes that everything that just happened was a dream. He wakes up after being assaulted by another fallen angel and finds Rias in his chamber naked. Issei learns that Rias is actually a devil and that she has reincarnated him as a devil as a result of Yuuma's murder of him, making him her obedient servant.