Lucifer, formerly known as the Seraphim, Helel. is a major character in the story, "DxD: FINAL" He was the former leader of the Devil Faction before becoming apart of the Expanse, and emerging as a powerful demon unlike any other. He is considered to be the strongest of all demons, known to all of them as their king. Alongside Merkabah, Lucifer is one of the two major antagonists of the story, and desires Issei Hyoudou to his side.