Brief Answer:
Most probably folliculitis; will self-resolve

Detailed Answer:
Hello sir and welcome.

Thank you for writing to us.

I have gone through your query and attached image with diligence and would like you to know that I am here to help.

This pimple like structure is most probably an irritated/inflamed hair follicle, this condition is called folliculitis. In regions which are more often damp than dry, regions where we sweat more (Eg. groin, back, underarms, breast folds, etc.), regions where there is constant friction caused by clothing, and other such regions; hair follicles can get irritated and at times even infected due to the accumulation of sweat and dirt.

There is absolutely nothing to worry about in such cases as folliculitis is a self-resolving condition, and will surely subside on its own. What you can do to promote healing is the following:
-Keep the region clean and dry at all times
-Avoid wearing undergarments for a few days or wear only cotton undergarments to avoid friction and further irritation
-Application of a warm compress to the affected region
-Maintain good hygiene
-Take 2-3 sitz baths in a day, if possible with epsom salt in the water

In due time, this pimple-like structure will surely resolve sir. There is nothing to worry about. I hope you find my response helpful, please feel free to write back to me for any further clarifications, I would be more than happy to help you.

Best wishes.

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