It sounds like you are describing a benign cyst, such as an epidermoid or sebaceous cyst, which are common on various parts of the body, including the buttocks. These cysts are typically soft, smooth, and can be squishy to the touch. However, it is important to have it evaluated by a healthcare...
If this is indeed an epidermoid (sebaceous) cyst, then for a small one like this a mimimal excision technique can be easily used. Following numbing with a local anesthetic a very small incision is made made over the top of the cyst, the contents then are completely expressed, a probe inserted to...
As a dermatologist, I can provide some general information that may help you distinguish between a sebaceous cyst and a lipoma, but a definitive diagnosis would require an in-person examination, possibly supplemented by imaging studies or a biopsy.
Sebaceous Cyst: Typically, these are...