i like this song.
well, of course i do. that's why i'm posting it.
buut anyway it's by Larval Stage Planning, who's done themes for anime such as BakaTest.
HighSchool DxD Original Synopsis:
The story follows Issei Hyōdō, 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 devil, and from that day forward, he serves as an underling of Riasu, a high-level devil who is also the prettiest girl on Issei's campus.
If you're interested in watching HighSchool DxD, you can start here.
[*WARNING* It's quiiiite ecchi ^^;]