I am in the same boat, I've had one girl accually finish me all the way on a blowjob, but she had to finish it with a handjob to get me to orgasm, I think it's the thrusting theory BigJayz, but I saw a post on TFP (V 3.0 I think) that was the guide book for blowjobs, which I think if everyone followed that post's guidelines, no one would have a problem.
Oh and hands help out alot during those final moments
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