She may be a prefat. Anyone with bad habits and no exercise but still looks thin for now is a prefat. I particularly hate these kind of fat because its so deceptive. They look human but turn quickly. They will balloon up over the next few years. Most likely some poor sole will be hooked up with her (because she looked human at the time) and wake up one morning next to a hippo and gnaw his own arm off to get away. You can always tell a prefat by their behavior and stupidity.