There's a web site devoted to male masturbation that poses a 'question of the week', and one week's asked 'How have you had an orgasm without touching your genitals with anything?', or some similar question. I didn't post, but got to remembering...
I was 12, a 7th grader, in a backwater little town. Things were different then. Playboy magazine wouldn't exist for another 5 years and its crude predecessors weren't sold anyplace in that stern little town. The internet didn't exist. Us guys knew very little about girls physically, and most of that was wrong. We didn't even think girls had any kind of sexual response, and for that matter, their mothers had probably convinced the girls of the same thing. And, girls wore dresses, or blouses and skirts, to school. Not a written dress code: they just knew, no pants. Oh, and remember the old swimsuits with the panel in front that concealed any clue as to the contours of that mysterious place down there? You didn't learn anything at the pool. I did have one bit of education that had eluded most of my friends: I had a little sister that I had watched being diapered, several years before, so I KNEW!
There was this girl in 7th grade, call her Jan, tho she wouldn't have answered to that name. She was gorgeous, and rich enough to hang with a different crowd from mine. I was limited to staring a lot and smiling now and then. She must have been a bit of a rebel. She actually wore jeans to school, now and then. Boy's jeans, no doubt, and I suppose now that she still had a young girl's hips to fit them the way she did.
There was this class. Jan sat just to my right, in one of those old bolted-down desks where the seatback was formed by the desk in back of you and the seat hinged up to allow you to slide through with no obstruction.
There was this one day I remember. There must have been a break in the class, because I turned to stare across at Jan and give her one of my silly grins, and this time she kind of smiled back. Then she swung around in her seat, turned her legs into the aisle between us, grabbed her desk with her right hand and the desk back of her with her left, and leaned way back to have this nice luxurious-looking stretch. Now her knees were apart, and for the first time in my life, I could see her jeans pulling tight around that most mysterious part of her. I had encountered some of those lovely words like 'Mons Veneris' and 'vulva', and could relate them to my memories of my little sister, but here was all the soft roundness of a real girl, and my glorious Jan, at that. And there was all that mystery (and I knew the word 'vagina', too) and it was pointed right at me, one-thirty-second of an inch of denim and (doubtless) seductive satin underpants between her and my lusty eyes. BAM! lightning struck my little penis, and I had a stunning, explosive orgasm without even bothering to get hard. It was my first, and it would be a long while before I felt anything to compare. It had nothing in there to shoot into my pants, but my little penis did its best!
I haven't seen Jan for nigh onto 50 years, but that 3 or 4 seconds is right there in my memory, ready to rerun anytime I want a great orgasm. But she has never given me such an incredible no-touch one like she gave me by just leaning back in her desk.