Porn is visual cheat code to release brain opiates(endorphins)
for anyone with imagination. But people don't understand the idea
of "porn" is more broad and you can masturbate to anything that gets
you sexually excited, up to stuff like fish with open mouths -
things that are actually not porn but the mind interprets it as porn because imagination is fast and really good at recognizing
patterns/filling in gaps. There is fundamentally no difference between
memory of something sexual and memory of porn/hentai images, used
as masturbation material. Being on NoFap makes even images of
fully clothed woman feel really sexy, probably same primal mechanism
of mate-selection starting up on each potential object of affection
and simulated imaginary scenarios can be constructed out of mundane
non-sexual media - as some said "Porn is whatever excites the sex drive" and there is no shortage of fetishists making porn out of weird
stuff like dragons fucking cars and furry mice being eaten alive.