The contour of that part of your body is predominantly determined by underlying bone structure. This means changing the fundamental dynamics is often fairly entailed. Lip position is related to the teeth and tooth position is related to the mandible or maxilla. Probably the easiest is to work with fillers carefully augmenting your lower lip including the trough of the labial mental angle. On your front door view it appears you have a somewhat large upper lip compared to your lower lip anyway so adding some volume to your lower lip would probably look pretty good. Obviously volume could be added to upper and lower lip but for the concern would you describe that’s probably the easiest. Best, Mats Hagstrom MD