It's not upside down. She's just wearing it wrong. This is an underbust style corset. The pointed triangular part is supposed to meet in the middle, but under, her breasts. Hence the term "under"bust. This type of corset isn't supposed to give any boob support. The corset is way too small. It should be sitting lower on her waist starting just above her hips, but as you can see it's never going to fit around that giant fupa. Hence the reason why it's riding so high. Here is one that's a similar (but much cheaper looking) design that shows how it's supposed to be worn. My guess is the bottom line of the one the fat girl has is supposed to sit more flat, but her huge stomach is warping the boning and making it bulge out.  And here is another one that shows the same pointed top that she has, but without the curving bottom.