This is an attempt to codify an aspect I really like across multiple fetishes, and it can be stated plainly as either "Pleasurable body parts get a lot more pleasurable" and "Body parts that aren't normally pleasurable now are"
This can come from a multitude of different sources, most common, but not limited to, would be aphrodisiacs and hypnosis.
greentext examples to follow.
>Magical aphrodisiac makes girl cum at the lightest caress of her clit >Hypnosis curses a guy with a really pleasurable ass >Shaman amazon conjures a spirit that makes her muscles flexing feel like sex during training >Long sensorial depravation to they point of hypersensitivity at the end of it >Transformations where the person ends ups a slave to the desires of their new body >Neurosurgeon GF asks you for help in her research and she remaps both of your pleasure centers to your lips and hands
etc
If you take it to its logical conclusion, you could remap any human sense to be strongly tied with arousal, and there the fetish gets outside the typical hentai shenanigans and go you full synesthesia
The content I have managed to scrounge goes from implied, to tangentially related, as this is very rare.
