Have you talked to your boyfriend about how this irritates you and make you uncomfortable? They are your dogs and your feelings/concerns. He should be made aware of the situation or it could escalate.
Communication is definitely key, just be careful to not attack the friend whilst discussing his behavior with your boyfriend. Just let him know and maybe he can talk to his friend and get him to understand where you're coming from. I let my husband know if he does something with the dog that makes me uncomfortable and have no issue throwing out even friends if they hurt my pup. My best friend's boyfriend decided sliding my dog *pretty hard* into the front door was hilarious and he got the boot, I would have stopped him before that happened if I wasn't busy in a different room. We're all still okay and I think he'll never touch my dog again
People get watched very carefully when they are around my dog now.
So yeah, communication! It is very important! Or see if when you guys hang out it can be at a place where your animals aren't