In very different ways, weight loss and body sculpting both lower body fat.
For instance, you gain or lose weight when the fat deposits in your body grow and shrink. Thus, you will lose weight when fat cells shrink all over your body.
On the other hand, body contouring is not meant for weight loss. Instead, it only eliminates fat cells from a specific part of your body. In particular, it's designed for individuals who are at a near-normal weight and are looking to get rid of one or two stubborn areas of fat. Thus body contouring is a cosmetic solution and not a weight loss method.