My right bum cheek is bigger than my left. I want to have something done to fix it.

If the asymmetry is mild and the patient has reasonable fat stores then fat transfer into the smaller buttock cheek may be considered. However in otherwise lean patients or moderate plus asymmetry, buttock implants are the only reliable and permanent option. Many patients also choose to augment both buttock cheeks with implants. Glad to help. 

Asymmetry is a common complaint among patients seeking out cosmetic procedures. Fortunately, there are a couple of options for correcting them.  A Brazilian Butt Lift, or a BBL, is a two-step procedure that uses liposuction to remove unwanted fat from areas such as your abdomen, flanks, thighs and back (bra rolls), and then transfer those fat cells into your buttock to create the shape and size you're looking for, as long as there is enough fat to remove.  For patients with asymmetrical glutes, adding more fat to one side can help rectify the problem.  If a patient with an asymmetrical bottom is on the thinner side and does not have enough fat to transfer, I have used injectable fillers, such as poly-L-lactic acid, to increase the volume of the buttocks.  Poly-L-lactic acid stimulates the production of your body's natural collagen, which adds volume to the area that should last a few years.  Best wishes!

Thank you for your question. While it's hard to tell from the picture how big of a difference it is, you can see the proportions are different. You could definitely benefit from a fat transfer/butt augmentation into the side that is smaller to help the symmetry. I would recommend finding a board certified plastic surgeon for a consultation to address your needs.    

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 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 :)