Training and using your PC muscles is ,for me, an essential part of good sex. It helps you dicatate the pace, control your orgasm etc. If you feel the urge of a rising orgasm you can just squeeze it off, pause for a little while then continue rather that have it finish too early. With a regular partner you can get to the stage where, if you feel she will orgasm, you can hold back and as she orgasms just let it go and cum together,,very satisfying..
Of course its not just for guys and women can train up also.
In fact sets of training "dumbells" are available for women.
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