Based on your photos, you appear to have a relatively lean frame, so the main question is whether you have enough usable fat in areas such as the abdomen, flanks, back, waist, or thighs to create the change you want. A “skinny BBL” can be appropriate for some lean patients, but the result is usually a subtle contour improvement rather than a very dramatic increase in projection. I would not recommend gaining 10-20 pounds just to qualify for surgery unless that is a stable and healthy weight for you. If the extra weight is temporary and you lose it after surgery, some of the transferred fat and overall shape may change. It is usually better to be evaluated at a weight you can realistically maintain. An in-person consultation is needed to assess donor fat, skin quality, hip and buttock shape, and whether your goal is achievable with fat transfer alone. If there is not enough donor fat, options may include accepting a modest result, staging the procedure, focusing on liposuction contouring, or discussing non-surgical or implant-based alternatives with a qualified surgeon. BBL safety is also very important. Choose a board-certified plastic surgeon who performs BBLs frequently and follows modern safety standards, including placing fat only in the subcutaneous layer and using ultrasound guidance when appropriate. Ask to see examples of lean patients with a similar starting point so your expectations are realistic.