Stuck shed on burm...

[Squirtle]

My albino burm shed yesterday after school, and he got everything off, most importantly his tail and eyes. He still has a small amount of shed left, though, and it's on the bottom part of his mouth. It starts from his bottom lip, until the back of his neck. Anyone know how I can get this off? I tried peeling it off, but it's very difficult and looks like it'll hurt him if I peeled it off with force.