Likely one of the Kong movies was an influence. Or something along those lines. But my first real memory of being interested in this fetish came before I even knew about being sexually aroused.
I was playing in my room, pretending to be some giant creature or the like battling an army of my action figures. As was a staple of kids programing at the time I, as the giant thing, didn’t crush or trample the female figures. I captured them in my hand.
Still wanting to play with the other figures as I “rampaged” I needed a spot to place the female formed plastic figures. And my young brain thought, in my pajama bottoms. But the fell down the leg. So, in my briefs they went.
As I played the tiny lady shaped toys rubbed along my penis. Then suddenly my penis did something I never seen it do before, it got hard. Pressed against my briefs and pajama bottoms with several lady action figures pressed between them.
Now, I know what had happened. But at that time my young mind assumed since I was pretending to be a giant scary monster that I was somehow, in a strange way, scaring myself. And that had made my penis stiff in fear.
That is my earliest and slightly embarrassing first memory of having an interest in this fetish.