Flat Butt
If your butt is without curves, aim for jeans with some stretch, wide set pockets, and embellishments on the pockets to add curves, like these Calvin Klein jeans, $79.50 at Nordstrom. You can certainly find these styles at bargain prices, too, but not all online stores show the back detail, which is what's important here, so most of what you'll see are going to be higher-end jeans.