Once her pussy slammed down and engulfed his length he knew instantly he'd not be able to hold out long.  She was tight and wet, with muscles that seemed to know exactly how to squeeze his member.  As he began to climax, however, a look of concentration crossed his face followed by s amile that was a bit sinister.  Instantly it was as if a vice gripped the base of his cock.  This not only stopped his impending orgasm but turned the exquisite pleasure into an equally torturous burst of pain.   He  did all he could to hold in the scream, but he knew she could see his torment.  How she did what she did he didn't know and he didn't exactly care- he only knew he wanted it to stop.<br/><br/>“Please.....PLEASE....” he moaned through clenched teeth.  “I \think my balls are going to explode.  I'll do anything...ANYTHING just please make it stop!  Please....mistress.."