My First Cum

I had a thing for holding my pee, and masturbating would help me hold longer.  I was up in my room, bursting to pee but intent on holding it in, stroking away, when suddenly....!!  It felt different than peeing, and it was a series of wonderful pulses, and then I had sticky stuff in my underpants!  I knew what it was, of course, and it was a big thrill.  With some repetition I established a strong link between a full bladder and sex that I still have to this day.