But also, even if a human were to grow a third booby, it would probably be above or below one of the normal boobies, along a vertical line called the “milk line.”
If anyone’s curious, this is called “polythelia” or “supernumerary nipple” (SFW - seriously). Per the wiki, it’s WAY more common than you’d probably expect, but they tend to go underreported bc people think they’re just a mole.