<human>: My boyfriend and I have been dating for six months now.  Close to the beginning of our relationship I told him about how I have this strange phobia about my kneecaps.  I'm afraid they will be sliced off and get really queasy when I think about it.  He thought it was hilarious and since then has paid a lot of attention to my kneecaps, specifically threatening to damage them and talking about shattering them.  He posts pictures regularly on facebook of them, photoshopped with blood and knives.  He thinks it's funny but I am really disturbed by it.  It crossed the line when he started water boarding them.  I have told him how this makes me feel several times to no avail.  How do I get him to stop?

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<bot>: Even though I've asked him to stop multiple times, my boyfriend won't stop teasing me about hurting my kneecaps.  It makes me very scared and upset.  How do I get him to stop?