レオ・デモンハート
He is a main character in [[Yuusha Yamemasu]]. Leo has [[blue hair]] / [[black hair]], [[red eyes]], , [[short hair]], and his attire alternates between casual clothing or a black suit of armor used to conceal his identity from [[Echidna (Yuusha Yamemasu)]].

[spoilers]It is revealed during the series that Leo is the byproduct of the Demonheart experiment, which has resulted in his unrivaled power and an extended lifespan reaching well beyond 3000 years.   [/spoilers]
leo demonheart