Precum usually does the trick for me. If you're in a situation where there's no lube to be found, then start the hj with spit, if the guy is as horny as I get from this, then his natural precum should be taking over by the time that your spit is drying up. Keep pumping. Btw, the more I get pumped, the more precum I ooze, oh yah. If you then decide to switch to a bj, there's nothing tastier then a hard cock, all covered and sticky from precum. So I've been told.
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