Yes, Mark has a demon form. We originally had the concept of an angel, and this is it.

Original description: The demon takes more of a human shape to it with its legs similar to an animals hind legs with dark blue-grey skin and it twice his size, body fat converted into pure muscle, claws on hands and feet, a tail similar to a raptors only with a spiked club on the end, pointed ears similar to an elf, yellowish white horns similar to a goat but longer and sharper, long, spiked blonde hair, a long muzzle like a raptor, a row of sharks teeth hanging out each side, piercing golden eyes that glow demonicly, wings made of pure bone that as 3 times the length of the demon itself and it tears out of its clothing, leaving only ripped shorts and barefoot. It stalks the shadows and only protects its mate while destroying anything or anyone to come near either of them.