Inside bottoms (Futanari, bottomless, free use, poop)

"... Inside somebody else's bottom.

So, in this reality both sexes have a penis, you would use said penis to simply penetrate somebody's bottom, in order to pee inside. You can also have full on anal sex with that person if they so choose- even in public. You should also be bottomless and ready to receive somebody's pee, everybody else will be.

You also poop into other people’s bottoms as well. Everyone carries a special pipe that, when someone needs to, they shove into their butt to widen it up so people can poop into them. If somebody starts to feel too full, they can find a ‘Toilet slut’, a genetically modified human designed to convert any pee and poop they enters their butt into nutrients to live off of. As such, conventional toilets aren’t produced anymore. Have fun in this new world!

Also pro tip. always have lube on you."