I'm not sure why nobody said this after the first post you made, but there is definitely something wrong with his vent area. You need to get that animal to a vet. The picture in post #1 is definitely a medical issue and the most recent pic does not look good at all.
I don't mean to hit you while you're down, but this is why you should take your animal to a reptile vet when it's got something wrong with it rather than rely on crackpot advice from internet heroes to solve medical issues.