Exactly. I had the exact same problem.
Long story short, he was trying to pick up 2 chicks (not in same times). The first one, I bring her back to my place. The second one (2 weeks after), my friend pulled her with him and k-closed with her INFRONT of him. It was so priceless, he continued to dance close to them and he was hating bad.
If he does that it's probably because he's an afc. So just play your game. Make he feels like a child. For example :
Him - Hey it's my player!
You - Yeah talk to you later I have to meet up with *chick name*
Or if you're already with someone :
Him - Balbalbalbablab
You - Sorry man I'm with *friend's name*, I'll see you later.
A hand shake is good too. He will have no choice. If he does, he shows that you are in control and if he doesn't, he looks like a fool infront of others.
Just don't play his game. Play mind games, it's the best.
It's from experience and I don't consider myself a PUA, but not an afc.