Im specifically thinking about a guy that was on Rogans podcast years ago who was a professor in sex psychology n shyt like that
Basically he said you can rewire your brain to get off on anything if you're looking at it when you have an orgasm, doesn't matter what it is, you do it a handful of times and you're going to develop a fetish for it even if it wasn't your initial "thing"
Porn having so many fake roleplaying style videos can easily make a regular real world situation into a fetish if you tune into that shyt too much
Just looking at "models" on IG shouldn't be enough to have you busting on regular women at a grocery store, like I said even getting horny at a grocery store sounds like a super specific fetish or video this brother was tuning in to
Or maybe he had a freaky ex who would get him off in public so he just got accustomed to being bricked up everywhere except the bedroom