How to get rid of fat on sacral fat pad after liposuction? (photo)

I think liposuction of this area would be the best option. Certainly there are others, but liposuction of this area would give a much better contour of the area. I would review the options with your surgeon to at least get their opinion since they know what was done and operated on you. If you are not comfortable with your current surgeon perhaps seek a consultation with a different Board certified plastic surgeon at least to discuss the options after a complete exam. Good luck. 

this may just need a small revision or even Kybella +/- truscupt. I suggest seeing an expert in HD Lipo body contouring.
You need a formal evaluation by an expert in body shaping and contouring to determine what is best.  Traditional liposuction awake and smart liposuction are old methods and do very poorly for tightening skin or significant skin tightening or contouring.  Small problem areas can be improved slightly by these methods.  The best in body contouring not only removes fat with energy devices like VASER ultrasound but also internally heat the skin with radio-frequency devices such as J PLASMA/RENUVION, InMode BodyTite, ThermiRF to heat the under surface of the skin and tighten it at the same time as fat removal. These combinations are called 4D HIDEF VASER contouring and can only be done by a well . trained body contouring specialist. At the same time fat should be harvested, PRP and stem cells added and injected into muscles or indentations/cellulite to get body shaping and contouring.  This is known as a Brazilian butt lift when you inject the fat to the buttock for contouring and lifting, but fat can also be used in areas such as the chest/breast, arms/shoulders, calves and face.  Cellulite should also be treated with cellfina, sculptra, subcision and/or fillers such as bellafill, renuva synthetic fat, or sculptra.  If skin is very loose before surgery then it will need to be removed such as lower abdominal skin (tummy tuck/abdominoplasty), breast skin (breast lift), arm skin (brachioplasty).  Overall you need a full assessment, but simple liposuction alone will not tighten skin and needs a combination of various methods -- fat removal, skin tightening, defining, fat grafting, skin removal -- to get the best in body contouring and body sculpting.  Dr. Emer.

Thank you for your question and photo. That is a limited view, but does show a large lower back fat pad. This should've been treated at the time of your surgery. this can be completely removed with liposuction only. I would use a drain postoperatively and a compression garment with foam pads for extra compression. See a board certified plastic surgeon for an in person consultation/evaluation. good luck.