The Japanese girl squeaks, but obediently lets herself be pawed. These noises only encourage the guy to stick his dick in her mouth and make her suck him. Groaning and sucking, she turns him on even more. Oh, I'd love to put a pepper up her ass. That's the kind of cat you should let your friends roast too.
Well, if they're friends, they're allowed! What if she needs help in the future, or will be bored - they can always pull. The main thing is for her boyfriend to enjoy it.