This is a relative guideline when judging whether or not a woman is fat. If her belly sticks out further than her tits, she's fat. But if her tits go out further than her belly, she's not.
Working example of Tit to Tummy Rule:

A woman with "A" cup sized breasts and a mild fat over pussy area (FOPA) can be considered fat, while one "C" or "D" cup with the same FOPA wouldn't be. Breast implants are highly encouraged to reduce the amount of fat bitches in the world.
by Cursed Irishman April 30, 2009
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