The third son of the Phenex house, one of the respected families in Hell. He was suppose to marry Rias in an arranged marriage between the Gremory and Phenex family but Issei disagreed and challenged him to a battle. Issei got beaten in one hit by one of his Pawns. Rias then agreed to have a Rating Game with Raiser to settle the matter of the marriage and get revenge for attacking Issei.

Spoiler

He defeated Rias in the Rating Game by beating up Issei until Rias surrendered. He was then beaten by Issei in the wedding ceremony using a combination of his Balance Breaker and using the Boosted Gear to amplify the effects of holy water and a cross which he brought with him.