First off she's leaning so you have a bad angle, but even still her back is arched and her butt comes out as far as her back compared to where her waist is. Not only that, but once again, you can tell from the front that she has a large butt and thighes. You can't see it that great from the back because they don't put definition on like butt-cheeks or even add anything that resembles a crack (where there is clothes) like in eq1 or WoW, so you don't have a reference point at all really except from the front where you can see the hour glass figure.
