I think you should tell him to stop and when you say this to them, you should say it in a serious voices that make him know you are not interesting in him. If he does not stop, tell your friend about his attitude toward you. He did this to you because he does not respect both you and your friend. If you love your friend you should let her know and kick him out. He does not dersve the love from your friend or any girl especially good girl. Also if she is your best friend she will understand you. Best friend, would not fight over guy, at least in my case because they did not deserve that fight. I definetly think you should tell your friend because he is derespect both of you.