text: Hi, I personally would not tell my friend.  I hate to be the bearer of bad tidings, and sometimes friends don't believe you(don't want to believe it themselves.) You know that old saying, "kill the messenger"?  What I would do however, is stay away from her boyfriend and not put myself in a situation where the two of you were alone.  If he continues to come on to you, out of loyalty to your friend, I would tell him what he is doing is not acceptable to you.  Your poor girlfriend.  It is just a matter of time before she sees through him.