And don't forget to be safe when it comes to grabbing hair, or throats and stuff. Have fun, but use safe techniques.
Oh, and girls are different sizes just like men. I wonder if he's hitting your cervix. With the standing-man-behind position, you get real deep penetration, it's possible an average man might hit the woman's cervix. Just a possibility.
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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