It is quite possible that the young man has only a limited interest in the opposite sex and that the interest he displays that annoys her is a constant pleading that they become intimate. If this is the situation, i would politely tell him the truth. For example: "tom, i feel that your only attraction toward me is connected with your desire to gratify your lust and physical knowledge about females, thus, it is now time for you to spend more time alone or take more cold showers. If this is not the case, might i suggest that you stop trying to discuss a sexual relationship and find out what interests me more than sexual excitement. That's to say that your behavior is annoying me and robbing me of my serenity and self-esteem. Please find some new interests to discuss. Now, that was long and complicated. Let me tell you that if i had been born female and was being annoyed by a male friend, i would simply end the friendship or relationship asap. Do you want to spend your life with someone who annoys you? Dump the guy, please. Uncle rob....