Can you make up new names for testicles, penis, vulva and clitoris?

[AG31]

How are you going to make this make sense for the reader?

Even more important, is there a reason in the story universe why conventional English language words aren’t used by the characters or by the narrator?

If this were done in a regular old contemporary setting on Earth, with no in-universe reason given or no lampshading at the very least (no acknowledgement that this doesn’t match the in-universe conventions of other people besides the characters or narrator), then suspension of disbelief would be just about impossible.

Even if there is an in-universe reason, like it’s not our world, it’s a made-up language, it’s a cult, the characters are totally ignorant of the words for these things because of whatever reason and so made up their own, even with any of these in-universe reasons or whatever others the story might have, it’s still clunky and hard to succeed with such a contrivance.

I added a post above that I wasn't suggesting we actually use these names. It's just for fun.

 

[Kelliezgirl]

 

[Five_Inch_Heels]

" ... was laying on her back on the pool table, her legs up in the air. She had racked Kevin’s balls and her was driving his cue stick into her center pocket."

 

[TheLobster]

" ... was laying on her back on the pool table, her legs up in the air. She had racked Kevin’s balls and her was driving his cue stick into her center pocket."

Hopefully he practices safe pool and had applied some chalk to the tip first.

 

[Five_Inch_Heels]

As I'm reading this, Prince is talking/singing about a Velvet Kitty Kat. Geeee, I wonder what he's talking about?


Also:

"Kitty was mewling just a bit and beginning to weep some again. I used a tissue to wipe her off and was on my way. I longed for someone else's hand to be under my skirt tending to her."

 

[PennameWombat]

Late to the game, but. On the general point, in dialogue, everything is fair game. Including giving private parts actual names (such as my character Isabella, who refers to a certain part of herself as Izzy.)

But unless you do a fair amount of work to establish something in-world, doing it in narrative is much more difficult. It's not that you can't, but you have to provide context to get the readers to understand. Whether they like it or not is up to them.

xkcd's Fiction Rule of Thumb on this this subject