That is a very good story. It reminds me of the one and only time I gave myself an orgasm in public. I had joined a gym for the first time and was pleasantly surprised to find out that when using one of the abdominal isolation excercise machines, that I could tense my vaginal muscles the same way I do when I masturbate, except with no hands.
So there I was, "working out" and enjoying the effects of each series of reps when , at the end of the last series I had a blinding orgasm. I bit my lip to avoid moaning out loud and squeezed my eyes shut only to open them and seeing one of the gym's trainers looking at me with a very concerned look in his face.
I was still dizzy and could not talk, so he came over, steadied me and told me that it was normal for beginners to be very enthusiastic about working out for the first time but that I should take it easy the first few weeks.
By then I could breathe normally again so I thanked him for his concern and his help but to this day I can not look at him without getting a stupid grin across my face. I am sure the poor sweet guy thinks I have a crush on him.