Fat man or not, this is still an incredible image. That look of pain/pleasure on her face is quite exquisite.
Overall, this game has some of the best art I've ever seen in a visual novel. When's the last time you saw CG from a game that warranted the realistic tag? On top of that, most (all?) of the H-scenes that I've seen in the game so far are animated. While I haven't gotten to the scene that this image is from yet, I have little doubt that it will be animated as well.
(For anyone who wants an idea of what these animations look like, check out post #749370 and post #749623. While they ended up not being approved, you can still see the images if you click on the "Size:" link in the statistics panel under the tag list on the left.)