Yh just smile after you do it, and you can say which i've done before is "you owe me a drink" or "go fill it up" and just laugh if off as a joke lol or you could raise your hands and shoulders as if to say ' i don't know' lol...

What i did with one her mates (which was a guy) i chatted to him, being friendly and defusing the thought of me being a threat, saying something along the lines of (handhsake) "hows it going, what night is this etc" and chatting shit but keeping it light and funny lol ( i didnt ask how they know each other etc bcos then it looks like im going to hit on his mates) ...then hi5'd her girl-friend... and then opened the target..

hope that helps...