Hello and thank you for your question.
Could you please tell me how long you have had this patch?
Your patch actually looks like a friction rub due to rough sex. The patch you have does not look like any STDs (most common being herpes, syphilis, and warts). Friction rubs are very common.
To heal it, you can apply calamine lotion to sooth the skin and may use a tiny amount of Cortisone 1% cream. Of course, it would be advisable to avoid sex for a few days to let it heal (if possible), otherwise it will continue to get aggravated.
If within a couple of days you dont see improvement, I would suggest you get this checked out.
I hope you find this information helpful. Please feel free to follow-up with any other questions you might have.
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