I think it depends purely on how horny the guy is feeling when you go down on him...

My B/F is uncut and sometimes I can suck him off in 3/4 minutes... other times I can have him in my mouth for 10 mins and he still hasn't cum...

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Please tell me what you think to my stories. Tell me what they did for you... that should be a real turn on!! Feel free to chat to me if I'm online...