How can I stop getting so upset??? 10 POINTS!!!!....?

My boyfriend loves booty. I have a pretty large butt. So I know he likes it and he always tells me. The thing is....he LOVES Niki Minaj. And if you know her, she has a fat butt. My boyfriend raps so whenever she comes on the radio he turns it up all loud and she is like his dream girl. A lot of the time he will just mess with me because he knows I get a little jealous. The thing is...its never going to happen. She is like a fantasy you know? But I get so jealous. I am happy with myself and my body, but still, it makes me a little insecure. Or if someone on the tv is good looking he will make stupid gestures just to mess with me. Because he knows I get jealous. What do I do? I have talked to him about it and he apologized but a few days later he will do it again. I find it kind of funny, but It still hurts. Should I act like it doesn't bother me? Cause the only reason why he does it, is to MESS with me. Should I do something back when I see a good looking guy and teach him a leason??