The experiment.

Over the past weeks, you've hooked up with your usual fuck buddy Nate, from the apartment upstairs. He's got a great dick and his dark skin and dreads are real turn on, but your dick stayed its usual size and he didn't go cock-wild after one taste of your cum. (Well, any more cock-wild than is usual, that is.)

There was a hot twink you banged in the locker room at the university recreation center. He was totally infatuated with your girthy monster and he loved the huge load of spunk you pumped onto his face, but that was all normal too.

A couple of twins at a frat party you went to--that was a mistake, you are way too old for frat parties--spent the better part of a night worshiping you cock with everything they could put it into, but it was merely fantastic sex, not supernatural.

The only logical conclusion could be that Craig himself is somehow part of what makes the "magic" happen, so to speak. You've been holding off trying to initiate anything with him again, you are afraid the first round diminished his essence too much. He's already a little smaller, a littler less hunky, and a little less smart. What if you did real damage to him the next time?