Diodora Astaroth

Diodora Astaroth is the former supposed heir of the Astaroth Clan & the younger brother of Ajuka Beelzebub. He is one of the main villains of Highschool DxD Volume 6 light novel & its anime adaptation Highschool DxD Born & the one responsible for Asia Argento's demise.

Appearance
He is a gentle-looking, handsome young man with blonde hair in the light novel & dark green hair in the anime. He also has a big deep scar on his chest which he injured himself to turn Asia into a heretic as part of his plan. He is usually dressed in noble clothing.

Personality
While appearing to be a gentle, well-mannered young man, Diodora is in fact a narcissistic, sinister, vile & wicked demon who would do anything to get whatever he wants. He is very obsessed with nuns & holy maidens as most of his Chess Pieces are all former nuns & holy maidens he had acquired all over the world by being the cause of their excommunication. He enjoys seeing them suffer in pain, sadness & despair as he finds it an ultimate form of entertainment.

He is also shown to be heavily disgusted with Dragons and those associated with them, as he calls Issei a "filthy dragon" but after suffering his defeat on him, he becomes fearful of him & dragons.

Trivia

 * In the manga adaptation of Highschool DxD, Diodora makes a cameo as one of the guests in Rias & Riser's engagement party.