Speaking my love language here, hence my username
A friend from school and I experimented for about a time (we were around 17-18). He had found a few porn magazines from his dad and we ended up masturbating on separate beds, which was really exciting ofcourse. (we both presumed being straight, i found out i was Bi after this encounter). We did this a few times, but always under the covers. He always put a towel on his belly and I remember seeing it being soaked when he had cleaned up. One day though I offered to jack him off.
When he finally came after about two minutes, his load was insane. Big, voluminous spurts of thin watery semen. All I remember is that his entire chest and belly were covered in cum. A pool had formed in his belly button and was overflowing on one side and down to the bed.
We went to sleep, and the following morning, confused but excited, we started fooling around and tickling eachother and i noticed he was rock hard. I ended up jacking him off again and within a few minutes he came, just as much as the first time. When I asked him how he came so much he just said he felt his body making a lot of fluids when he got turned on, and he always came like that. I told him how much it excited me and he became hard again. This time jacking himself off and cumming again, and it was about as much as last time. Genuine hyperspermia that was, his body just produced waaay too much seminal fluid.
We fooled around for about a year and played some edging and denial games to see how much we could make eachother cum. These stories still bounce around in my head sometimes and it's 100% where I got my fetish from.