Hey, I think I found a manga for you.

I was foraging in the dollar boxes at the local comic paradise, and turned up an issue of Viz's flipped & translated Bastard. "Heavy Metal Dark Fantasy", the cover said proudly.

Action, gore, and black comedy in abundance, lots of 4th wall breaking from the author, and spells called things like "Wall of Guns And Roses". And the big villain is called "Dark Schneider".

Here's the wiki wrap:
Bastard: Heavy Metal Dark Fantasy

It's completely awesome and you'd love it.