I've found that if I have sex with my girlfriend about 3 times (maybe one hour total over a two hour period) she starts to say she is sore. Granted, I am unusually large and she is unusually small, but is this normal? In the past women normally want more sex than I can provide, so I wonder if a girl being sore by the 4th time can mean infidelity. Then again I have had some girls who I made sore in the past, and to be honest, there haven't been too many I liked enough to have sex with them 4 straight times.