If they are large I would have them looked at, it could me MRSA, which is staph and can become a big problem. If they are small pimples then this is normal and could be ingrown hair or dirt in the pores that need to be clean. Hope this helps.
Hello,
These pus bumps on buttocks can be due to boils. Boil on buttocks is usually due to plugged sweat glands that become infected or by an ingrown hair.
Apply warm compresses on the boil and keep the area clean. Drainage of the boil is done only when it becomes soft and forms a head. Take some over the counter pain reliever and consult a doctor for examination and antibiotics prescription. If there are recurrent boils, then please get your blood sugar levels estimated.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.