P.F.M.D
A person who looks slim, but can eat like a pig and still be mostly thin. Their arms are like two rolls of fat.
"She’s like a ghost who eats donuts for breakfast.", @DonutQueen
Tweet: "Her arms are like two sausages. P. F. M. D.", @SausageLover
DM: "You think you’re fit? I could eat you and still be fit. You’re a P. F. M. D.", @FitBull