imagine the transition, from an Interstellar-esque 100% corn based diet, to an American diet. One full of fast foods, diverse ethnic cuisines, spicy food that is hard to stop eating, junk food, candy, burgers, mountains of meat, microwave dinners, and high fructose corn syrup. No wonder Star puts ridiculous amounts of sugar on her burritos; she has no fucking clue how to eat on earth.
She must be using some pretty powerful illusion spells to hide her fatness. I ship her with Ferguson. I just like him as a character, and I used to wish he would get taller and slimmer, and become a genuine love rival for Marco. But now that I realized how fat Star is, I think he can remain chubby, and he and Star can be fat together.