From what I've seen from my own albums, they get the same exact boobs as a fat guy. They kind of go off and down to the size and the fat joins with some underarm fat in front of where your lats are supposed to be. Like you see on sumo wrestlers.  There's one fatshion tumblr fattie, I call her Ms Cleavage of the Year, her boobs are almost completely under her armpits. EDIT: Oh and there's Ms Sumo Tits. She takes millions of selfies and thinks she's the hottest shit around. Just look at her IG.