Sentouin D

A rebellious foot soldier from the villainous army in the sky fortress that arrived 13 years ago, he is a Duster with transformative and regeneration abilities alongside his fellow foot soldiers who vowed to defeat the Dragon Keepers by infiltrating their organization and ranks. He takes on two disguises for most of the series; one is an appearance of an average black haired teenage guy, and the other as Hibiki so he can use his identity to infiltrate their ranks easier.

(Source: Wikipedia)