He later joins the Occult Research Club as he strives to rise up the Devils' ranks to fulfill his dream of building a harem and becoming a 'Harem King'.
The series revolves around Issei Hyoudou, a perverted high school student who is reincarnated into a Devil by Rias Gremory after being killed on his first date. High School DxD is a Japanese light novel series written by Ichiei Ishibumi and illustrated by Miyama-Zero. You can give comments or suggestions on what to improve in the wikia here.