What can I do to fix this giant roll above my buttocks? BBL/body contouring or lower back lift? (photos)

Lipo will not improve the laxity of the skin but might be reasonable.  Without additional photos, unable to comment regarding a BBL as unable to see fat stores. Consult via email or Skype with a board certified PS to determine the best treatment(s) for you to reach your objectives.

Dear yagurlmeral,
it is hard to tell for sure without an examination. Based on your photos, it looks like you would benefit from a liposuction. If you are considering a surgery, I would suggest you to consult a board-certified plastic surgeon. Only after a thorough examination you will get more information and recommendations.
Daniel Barrett, MD

Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

Thanks for the question. 
In this regard, I recommend you waist and back Liposculpture, getting better curves especially in the waist, improving your body contour.
Finally, I suggested take the fat we get and transfer to the buttocks and hips, to mold them and get better volume, contour and butt projection, is that we know as "Brazilian Butt Lift" (BBL).
Kind regards

Hello dear!
Thanks for the question and provided information as well.
Based on your pictures, you are a great candidate for liposuction with BBL, and I think you'll get very good results.
Liposuction allows your plastic surgeon to transform your entire shape. You can improve your abdomen, back and flanks, and of course your buttock, to give you a nice heart shape.
In general, you need to be physically healthy and at a stable weight, have realistic expectations, be a non-smoker and your BMI needs to be 33 or less.
l recommend you to make an appointment with a board certified plastic surgeon to talk about your goals and anything you need to know.
Good luck :)

This may be corrected with a BBL and high defintion VASER liposuction. Based on your pictures, you are an excellent candidate for a Brazilian Butt Lift (BBL). The optimal BBL outcomes are achieved with: 1) use of VASER liposuction to harvest the fat, 2) a closed looped system such as Puregraft to process the fat, and 3) strategic micro-packet transplant technique. These three processes have demonstrated over 95% fat graft take. This means that your results will be stable as long as you maintain your weight. As an official VASER trainer, I am routinely referred unhappy BBL patients. One of the most common reasons for disgruntled BBL patients is that patients are not able to accurately communicate their desired buttocks goals to their surgeons.  A buttocks assessment tool can be an invaluable tool to communicate to your surgeon the exact buttocks size and shape you are desiring. A Skype or FaceTime consultation with a BBL specialist can help you get an accurate recommendation and pricing. 
Respectfully, 
Arian Mowlavi MD, FACS
Realself 100 Hall of Fame Inductee
 

Your contour problem represents both fat distribution our skin laxity. The best treatment outcome may require both skin excision and Liposuction with fat transfer.Skin laxity contributes more to body contour than people believe. You can confirm this by simply pulling up tightly on the skin above they are your concern.Is pulling on the skin above the area of concern fixes the problem or a greatly improves it then skin laxity is contributing significantly or primarily to the problem.If pulling on your skin has minimal impact then it is more likely primarily based on fat distribution.Considering your history of weight loss a BBL alone will most likely not correct your contour but may improve it.Skin laxity is the number one reason we fail to get great results with both Liposuction and fat transfer procedures.Loose skin contributes to contour and inhibits contour improvements from fat manipulation.I suggest having a few in person consultations. Look for plastic surgeons who either demonstrate the above indication for skin removal or at least discuss it.Nobody wants long scars and plastic surgeons aren’t thrilled about creating them.If the primary problem isn’t treated then you need to accept  that results will be limited.Best, Mats Hagstrom MD