So Futa is the Future??

[Meaning Less]

I think there's also the hentai logic of making more body parts extra-sensitive, stacking that 72-hit pleasure combo. Aphrodisiacs, drugs, X times more sensitive Y magic or mind control, multiple or adventitious genitals...

True, give me a character with extra sensitive ears and I will be rubbing those ears nonstop

I don't care about what body part we are talking about as long as it makes them lose their minds when rubbed.