How can I correct this empty space on my right butt cheek? (Photo)

Though an exam would be necessary, this may represent fat necrosis. These areas can be surgically excised.  Based upon your description and goals, contour irregularities can be fat grafted.

The best way to achieve a celebrity-like butt and hips is a Brazilian Butt Lift. A Brazilian Butt Lift is a procedure where excess fat is liposuctioned from different parts of the body and moved to the buttocks. This reshapes and adds volume to the butt while keeping a natural look. Final results are permanent and generally seen about 6 months after the procedure.

Dear milf160,I understand your concern. However, without a proper assessment it would be difficult to determine what is wrong. It is best that you visit your plastic surgeon for further assessment. Only after thorough examination you can get proper recommendations and advice.Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

Hello dear!
Thanks for the pictures and provided information as well.
Based on your photos, you are a good candidate for fat transfer, to fix your problem and improve your buttocks, and I think you'll get very good results. 
l recommend you to make an in-person consultation with a board certified plastic surgeon for a proper answer and to talk about your goals and anything you need to know.
Good luck :)

There are multiple reasons there is still a dimple post-BBL. It is possible that the fat cells did not take to that area. However, I would recommend speaking to the surgeon who performed your BBL procedure about your concern. He will be able to recommend the best course of action. This issue may be able to be corrected with a revision procedure, but your surgeon would be the best person to make that call. 

From your photo, it appears you are concerned with the cellulite on your buttocks (especially since you said it was present pre-op it is less likely fat necrosis or scar tissue from the surgery). Yes, cellulite typically gets worse over time with aging. It can improve with some weight loss but not in everyone as even very thin people can have it. You are correct in the fact that a BBL does not correct superficial irregularities such as cellulite. Immediately after a BBL the swelling makes things look very smooth and shiny. By 3 months when the swelling is gone and the 30-50% fat volume loss has occurred, the cellulite resurfaces. 

Thanks for the question and photos.Many times it may be scar tissue which holds the skin down and needs to be freed.  The loss of fat following the procedure is normal and you should expect around 30% to be absorbed.A physical exam would answer many of these questions.Best of luck.Dr T