Brief Answer:
Furunculosis is most likely possibility

Detailed Answer:
Hello. Welcome to healthcaremagic.com.
I have read your query. I understand your concern.

I have seen the attached photograph also.
It seems that you are suffering from a condition called Furunculosis. It is bacterial infection of skin involving the hair follicle and surrounding areas. Penile shaft is hair bearing part of the body. It gets very easily infected by improper hygiene or untrimmed hair.

In such cases, I prefer to advise topical antibiotic cream like mupirocin 2 percent over the affected area. Also oral broad spectrum antibiotics like cloxacillin is started.
Keep the area clean by using soap and water.
Get your blood sugar levels done.
Regularly trim your hair.

I will advise you to visit your doctor so that he can do clinical examination and give you prescription.
You can share my opinion with him.
I hope it helps.
Stay healthy.

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