Kuoh Academy is a former all-girls college which has lately turned coed, but it's a solution. Demons and unknown to ordinary people, angels, fallen angels constitute section of the pupil populace. One Issei Hyodo, of these pupils, is a lecherous second year individual pupil who lives a lifestyle that is peaceful. After a normal school day, Issei is unexpectedly asked on a date with a girl named Yuma Amano. After their date, Yuma makes a startling request and brings Issei to a neighborhood park. She reveals herself a fallen angel, as Raynare, and she attempts to destroy him. Using her card that is summoning, Rias Gremory, a buxom third year student at Kuoh Academy, animates him. Issei wakes up the following morning, believing the events that happened were all only a dream. Promptly after waking up and being assaulted by another angel, he sees Rias nude in his chamber. Rias says that as an outcome of his death in the hands of Yuma, she's reincarnated him as a demon, becoming his new master along the way and discloses to Issei her true identity as a demon.