Right buttocks, big.
Thank you for your question and photograph. It's difficult to evaluate your skin through this type of forum, but from what I can see, it looks like a large flat nevus (mole). Lesions of that size, surgical excision will be difficult as the resulting scar can be large. There are laser treatments available but results vary per individual and often times, multiple treatments are needed. I highly recommend you consult with a board certified dermatologist or plastic surgeon to have you mole evaluated and to discuss appropriate treatment options for you. Take care and good luck.
