Joking about engaging in sexual activity with someone, especially when it's one-sided or the other person is not interested, is inappropriate and disrespectful behavior. It can make the person on the receiving end feel uncomfortable, objectified, and disrespected.
There could be several reasons why a guy might engage in such behavior:
Lack of awareness: The guy may not realize that his jokes are making the girl uncomfortable or that they are crossing boundaries.
Social pressure: Sometimes, individuals might feel compelled to make inappropriate jokes to fit in with their friends or to seem more "macho" or "cool" in their social circle.
Inappropriate sense of humor: Some people may have a misguided sense of humor and think making offensive jokes is funny, even though it is hurtful to others.
Testing boundaries: The guy might be testing the girl's reaction to see if she shows any interest in him beyond friendship.
Regardless of the reasons, it's essential for the girl to communicate her discomfort and set clear boundaries. She can express her feelings calmly and assertively, explaining that such jokes are inappropriate and hurtful. If the guy is a true friend, he should respect her feelings and stop making those jokes.
If the behavior continues or escalates despite her communication, it might be a sign of a deeper issue, and she may need to reevaluate the nature of their friendship and consider whether this person is genuinely respectful and supportive of her boundaries and feelings. In any case, no one should feel pressured or uncomfortable due to inappropriate jokes or behavior.