Diehauser Belial

Diehauser Belial is a prominent character in High School DxD, a pure-blooded Devil and the former head of the Belial clan (one of the 72 Pillars).

He is widely known as "The Emperor" or the undefeated Champion of the Rating Games, holding the top rank for a long time due to his exceptional skill and power in the demonic competitive battles.

He has a graceful appearance with grey hair and grey eyes, and his personality is described as humble, polite, and respectful toward opponents as well as rising young Devils.

His signature ability is the Belial clan's unique power called "Worthless", which allows him to negate or nullify certain effects, objects, or powers (making him extremely formidable even against high-level opponents).

He appears mainly in the later parts of the series (light novels and the HERO anime season), where his role involves more complex alliances and motivations tied to the underworld's events.