How do I get my other fixed male cat to stop peeing on blankets?

He doesn't have a UTI but is it because of domince over the other cats?

I can't say its dominance. How old was he when you got him fixed? Anyway, here's the thing. Cats are WAY picky. Some cats feel that their litter box isn't quite up to their cleanliness standards. If your cat thinks that, then he will be peeing on your things, kinda like a "how do you like it?" type thing. If the problem continues, you should probably just keep him for an outside cat.

Well, I would try getting attracting litter to bring him back to the point.