Brief Answer:
Most likely folliculitis; could also be ingrown hair

Detailed Answer:
Hello sir and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. After examining the attached image I would say that this is either an ingrown hair or folliculitis (inflammation of a hair follicle, which can or may not be accompanied by infection of the hair follicle).

Folliculitis is more likely and occurs from either of the following activities:

+Shaving or hair removal from the region
+Friction from clothes, inner wear, masturbation, etc.
+Leaving the region damp for long periods of time especially common during hot summers
+Poor hygiene (e.g. not changing inner wear frequently enough, not taking a shower frequently enough, etc.)

I would recommend the following:

+Apply a hot compress to the region (as tolerated) several times a day and the presentation should self-resolve without requiring any medications whatsoever
+Trim the hair in the region to avoid the hair from getting pulled which can result in such a presentation
+Keep the region clean and dry always, if you sweat then clean the region and change your inner wear
+Inner wear not to be worn longer than 24 hours

There is absolutely nothing to worry about as the condition is self-limiting and will resolve on its own. I hope you find my response both helpful and informative. Please feel free to write back to me for any further clarifications, I am always here to help.

Best wishes.

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Brief Answer:
STD seems unlikely as per the description and location

Detailed Answer:
Hello once again sir.

With the given location and description an STD is unlikely, but for your satisfaction you could go ahead with an elaborate STD-panel which should help you to put your mind at ease. But according to me an STD is unlikely sir.

Best wishes.

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