Edgeplay. I looked it up at the library.

[ He did research, who is this absolute wizard in Molly's arms? Hearing that moan, he sucks on the same spot harder before elaborating. ]

I have to bring you to the brink of coming then stop you doing it, over and over. [ His lips trail up to an ear, finding the right angle to take in the tip with a husky chuckle. ] I think I can do that.