Basically, you push your boobs together, then have your guy, uh, slide his penis in between them. He then moves exactly as he would if he were penetrating your vag. It might sound painful, but it’s actually probably not that bad for you – unless he’s getting a little too grabby with your breasts – and would probably be more painful for him – think dry humping, but literally dry. Ouch. If you want to try it, be sure to put some lube on your chest so you don’t hurt yourself or your bae. You can either use this as a form of foreplay, or even have your guy finish while doing it. If he does finish, you might get what is called a “pearl necklace” AKA when a guy finishes on your chest. So clever.