Doggy Style

Everytime I have sex with my SO its great until he tells me to throw it back. We had sex yesterday, we started off in missionary then he told me to turn around so he can get it from the back. Within 2 minutes he cums. After he came we got in the shower and he happens to apologize for cumming so fast, he says I couldn't help it, it felt so good, hes he cutest thing ever. The Theres something about back shots that sets him off. Does anyone else experience the same thing?