High School DxD (2012)

The story follows Issei Hyodo, a dim-witted, lecherous second-year high school student who is killed by a girl on his first date ever. Issei is reincarnated as a demon, and from that day forward, he serves as an underling of Rias Gremory, a high-level demon who is also the prettiest girl on Issei's campus.