Monster Soul Vol. 2 (manga)

Coming upon a young boy whose kingdom was stolen by monsters from Hell, the Black Airs answer his plea for help and race to the underworld. New enemies awaken old memories, and the Black Airs find themselves in a bind when a ferocious chimera stops them in their tracks. Aki and company must find a way to come together and defeat the monster, but it won't be easy, as the enemy may not be what he seems...