Welcome to Health care magic. 1.They are infective cause with collection of pus within - most possible cause could be hair follicular infection. 2.Which needs an antibiotic treatment, in case of larger and recurrent ones - it need a small incision and drainage. 3.But once for all remember - do not press or scratch the lesions / lumps, you will only make it complicate it. 4.Avoid cloths which cause friction / irritation that will also cause recurrence - use sod nature of the clothing s. 5.Maintain local hygiene, keep area clean with antiseptic liquids, avoid shaving until completely healed - mean while use trimming instead. 6.If you follow above it will gel in complete cure. Good luck. Hope it helps you. Wish you a good health. Anything to ask ? do not hesitate. Thank you.