boil on buttock

i am getting lot of boils on my buttock and few of the boils got very nasty and due to which it had started paining on to the right side of my leg under the testicles.

[Dr_Aparna]

Hi,
Boils and carbuncles are painful, pus-filled bumps that form under your skin when bacteria infect and inflame one or more of your hair follicles. Boils which occur in clusters are called carbuncles.

Boils can occur anywhere on your skin, but appear mainly on your face, neck, armpits, buttocks or thighs — hair-bearing areas where you're most likely to sweat or experience friction.

People  who have diabetes, a suppressed immune system, acne or other skin problems are at increased risk of developing these lesions.
Boils usually form when one or more hair follicles become infected with staph bacteria (Staphylococcus aureus).  These bacteria generally enter through a cut, scratch or other break in your skin.

Most boils run their course within 4 to 10 days.  Applying a warm compress can help alleviate the pain and hasten draining of the pus.
Once the boil drains, the area should be washed with antibacterial soap and bandaged well. The maturing process may be accelerated by applying Ichthammol-based salve.

You will have to get it examined if the boils that are very large, haven't healed in two weeks or are accompanied by a fever.
You may require oral antibiotics to bring about a resolution in such cases.

ref:http://en.wikipedia.org/wiki/Boil
ref:http://www.mayoclinic.com/health/boils-and-carbuncles/DS00466/DSECTION=prevention