This crease is created inadvertently by many surgeons when doing liposuction of the outer thighs.
The reason the bottom of the butt cheek blends in with the back of your thigh is that there is fat there acting as a column of support for the buttock cheek. If you eliminate that fat column support, the butt cheek sort of rolls over the skin of the upper thigh. The butt does descend a little when this happens.
The solution to your problem is to liposuction the upper part of the back thigh and the saddlebag. The buttock will then round out as it descends.
Contouring the buttock is a new area in plastic surgery, so a lot of the questions patients have don't have procedures with a long track record. Be sure you get a surgeon who does a lot of Butt Lifts.
