It finally happened.

After not allowing myself to cum for 5 weeks, I was bottoming and while he was fucking me missionary my dick dribbled out a TON of cum, aka a sissygasm. It ran down my stomach into my bellybutton. I was full on limp and my dick was not touched the entire time. It felt like a pressure then a soft wave of warmth followed a few seconds later by an intense pleasure pressure, then slowly faded into a sore feeling. After years of trying to do it with toys and never succeeding, I guess I needed a real man with a good dick.