I wonder what those other two after bat are? it looks like a sand clock and a clawed gauntlet. Wonder what the last move is?
Also, why does it have to be "Devilish"? Gabuella has a few real nifty abilities too, most notably the ability to turn into smoke, a smokey/fiery Dragon, and the ability to make dark energy whips.
Trevorcard on the other hand has a few not quite as grand powers, which involve turning into mist, a bat, and a wolf. AKA traditional vampire powers.
Y'know, I think the way this will play out is Gabe turns him, and then you fight him as Simon, kinda like how Trevor fights Alucard in CV3, and once you beat sense into him, he joins the party. Or something. Maybe.
Also, he isn't blue. I think it's supposed to look like a pale almost grayish color. It looks all wierd probably because it's a camera photo of the screen.
As for being bare chested, Im pretty sure he was.