Quote:
If the guy just does it once he is probably joking around, laugh it off - he means no disrespect.
If the guy persists beyond what you are comfortable with the situation needs to be escalated. Immediately alert this guy to the fact that he crossed your line, and that he is in serious physical danger. I try to remind people that blatantly disrespect me that they have friends and family, long with other people who care about them. I make it clear that its never a good idea to do things that makes them risk losing the important things they have in life.
On the same note, here are a few lines that would make Tony Soprano proud:
"Careful, boy, you are about to get more than you bargained for."
"You're not the first guy to say that to my girl. If memory serves me right, the last one woke up to the sound of his own screams as his flesh burned on a misterious house fire."
"That's cute. Hey, honey, remember the last guy who said that to you? I heard he's out of the ICU and can almost eat solid food again."
"Do that again and you, your family, your friends, your whole fucking hometown, will end up on the bottom of the river"
or
"I believe it's time for you to leave. Or do you want to stay and meet my friends Mr. Smith and Mr. Wesson?"