With a skinny model who has a very curvy bottom.
This was done with two lights -- one angled to the background and the model, turned up very bright, and one behind the photographer and up high and turned down low -- about 5 stops lower.
This is not the normal lighting style I prefer but I wanted the image to be a bit harsher and a bit blown out. Matter of fact, this might look too professional for my tastes. I'll have to do this again at a later date, and make it a bit rougher.