High School DxD: The Divine Hakuryuukou

Nios is an otaku who has only befriened 4 people at Kuoh. He's also 10. He makes a bet with Rias. If he dies within a year he becomes her servant. And he gets killed by his untrusted girlfriend. He's reborn and seeks revenge. After his revenge succeeds he will then plan to get on top in devil society. Ocx harem. Abonded