There's talk in this video just after 2:45. She points out that he's uncircumcised (in response to something someone wrote in chat). Then she pulls his foreskin forward and says "look at that extra skin going over the head" before sticking her tongue inside the end of his foreskin and then nibbling on it.
The vid is mostly a bust in terms of sex as he isn't able to stay hard but there's some more play from about 10 min and foreskin nibbling from 11:15.
