A very small fat-transfer touch-up can sometimes be done with local anesthesia and light sedation, but a true BBL usually involves liposuction, fat processing, and careful fat placement over a larger area. For comfort, positioning, safety monitoring, and control of the procedure, many surgeons prefer IV sedation or general anesthesia even when the goal is a subtle "skinny BBL" result. With a BMI of 21.5, you may also have limited donor fat, so expectations should be modest and focused on contour refinement rather than major projection. Do not choose the anesthesia plan only to avoid fear; discuss your anxiety with a board-certified plastic surgeon and anesthesia provider. The safest plan is the one that allows careful liposuction, subcutaneous-only fat placement, and proper monitoring in an accredited facility.