Cuntballs is the result of intercourse between a mans balls and a woman's cunt. the balls are irreversibly stuck in the woman's vagina.
The only way to free the man is to remove his balls preferably with a rusty piece of metal. the balls will remain inside the vagina permanently.
The woman's vagina is now known as Cuntballs instead of the cunt.
Elisa: hows your asshole going?
Joe: Good thanks, how are your Cuntballs going?
Elisa: They're a bit itchy but otherwise pretty good