I've sent you a PM.
Yes it was very irritating. It was an automatic response that just happened during mb. I'm sure it was from memories of being tortured and abused. Mine was mostly contractions of my abdominal muscles (abs). But I suppose lots of guys get body memories in their rectal area.
I hope this illustration doesn't offend anybody. If you've ever had a male dog and you rub his back, he has an involuntary response of humping. This is the closest example I can give for it.
Edited by pufferfish (09/07/12 11:25 PM)