When a character's balls have nipples or are outright replaced with breasts.

If the body parts in question are shared between multiple people (acting as balls for one character and breasts for another character) then both breast_balls and testicle_breasts may apply.

Not to be confused with:

• testicle_breasts (when a character's breasts are replaced with balls)

Also see:

• udder_balls
• penile_breasts
• unusual_anatomy
• unusual_breast_placement