Aftoncest 

Incest between members of the Afton family from Five Nights At Freddy's

"Bro, I love aftoncest"
"What the fuck is wrong with you?!"

Aftoncest by Aftoning123 May 19, 2024

Autocest 

A new sin; the act of cloning one's self and having sexual relations with said clone

My brother had autcestual relations with his clone!

Isn't autocest a sin?

Autocest by Josh Malavenda November 5, 2018

autoincesturbation 

(v.)
To have sex with a copy/clone of an opposite-gender version of yourself.

Guy 1: Hey, if you could, would you do Autoincesturbation?
Guy 2: The hell is that?
Guy 3: Fucking a female you.
Guy 2: ...Totally.

autoincesturbation by DNottin September 6, 2013