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There are two likely reasons for his behavior - either he thinks that is the way to satisfy his partner, or (much more likely) he is only interested in his own satisfaction, reducing his partner to the status of something simply to be used for his pleasure. The only thing that can be done is for his partner to explain that what he does HURTS, and that she is not prepared to be hurt in future. He needs to know that if he does not change his ways, there will be no more sex - that's the botXXXXX XXXXXne. It would be useful to get him to read a book such as The Joy of Sex: The Ultimate Revised Edition which will give him a much greater understanding and make him a better lover a s well.