Now that I know what it is, how do I fix it?

Options
So, I have what is known as "high hips". Or my favorite term that plastic surgeons pushing lipo suction use, "violin deformity". How nice, eh? Its an inward slope between the iliac crest and upper thigh. Here is a picture.

jeans2.jpg?w=113&h=123

Mine isn't nearly as pronounced as this. I'm not sure if in my case its genetic, or what I'm hoping, is an underdeveloped muscle from an incomplete lifting regimen.

So I ask, is there a muscle there? Maybe the gluteus medius? (where the inward slope is) If so, what is it and what exercise can I do to bulk it up and smooth out my silhouette?

I'm 5'4" and 117. The more fat I lose and the more muscle I put on, the more pronounced it becomes. I would prefer NOT to lose anymore fat. And I have a good deal of muscle already. Not sure what else I can do.