We all know your first fap was on a movie. Now the question is: Which movie was it?

Super Troopers.

Specifically, the scene where he jacks off to the speedometer. I knew of masturbation then but never tried it. That set me off in wanting to experiment.

Highlander 3, the asian hooker getting fucked. Knew it was a shit movie even then

he WHAT?

Jodie Foster in Taxi Driver.
I fapped so often that it actually hurt.

Gets his hand going 90mph

You masturbated on a bus?

Not a movie per se, but this music video. (Sorry about paragraphs, only 20 lines allowed)
It was the early noughts, and I had just discovered WinAmp.
WinAmp had an integrated Shoutcast browser, which had not only a selection radio stations as they do today, but also a selection of music videos. And I could stream them through Winamp, for free!
This blew my mind. You mean I could listen to like 5 (FIVE) Linkin Park songs free of charge? As many times as I wanted? With the music video? With crappy picture and sound?
Remember, this was before the days of YouTube, let alone Spotify and other streaming sevices. If you wanted digital music, you bought it (for which I needed income and a credit card), or pirated it (Which I didn't know how to do), or you streamed it, like I ended up doing. I was quite proud of this discovery, the little turd I was.

Around that time I had a friend in school who was really into 80s rock. I suppose his father had a collection, and my friend got me into it in turn, and so I would look up bands like AC/DC.
And there were four AC/DC songs/videos, if I recall correctly they were:
And
Which is the one embeded in this post.
I would watch the Sattelite blues video, and every now and then this lady would pop up for a second or two. For example at 0:37 & 1:25.
And this, I swear to god, made me feel like I needed to use the restroom. Or atleast I thought so at first. I figured it out after a while that this was a differernt type of compulsion, so I would pause the video, and Winamp would fade to a halt, so I had to time it a split second in advance. And if I missed, I'd have skip back on the video, and reload the stream. Sometimes the stream would crash. It was all very inefficient.
I didn't fap to it per se, my first fap and ejaculation was driven by pure imagination, and at this point in time I hadn't quite figured out that stroking was a key part to ejaculation. This just makes for a better, and much much sadder story.

I still wank over movies. I have absolutely no interest in porn

Yeah, it was a coach bus, with the dvd player and a bathroom

And people didn't comment on the fact that you fapped in the bathroom? And presumably left a big mess?