Its okay to be jelous of your gf's guy friends. They can totally screw up a couples relationship. I think Sashas a smart girl and if she loves you she wouldent leave you for another person. That is not love. Let her kno you dont like this guy and your a bit jelous but you wont stop her from being his friend, just to let her kno how you feel and not as an order. If she loves you she will understand ur feelings and if the guy puts a move on her she'll remember exactly how you feel and hopefully say No.

She may find it sexy lol Have a good one penguin!