Brief Answer:
It looks like a Sentinel pile.

Detailed Answer:
Hi,

From your description, it doesn't look like a serious problem. As per your description, it looks like a Sentinel pile. It also looks like a polyp , but commonly occurs outside the anus, in the midline. It occurs due to Fissure in ano. However it has to be removed surgically.

Let me know if you think this is something else.

You should take high fiber diet, drink plenty of liquids, eat fresh fruits and vegetables. Your stool should be soft. This will heal the fissure.

Please consult your Surgeon, get examined clinically and proceed accordingly.

Hope I answered your query. If you have any questions, I will clarify further.
Wish you good health.
Regards

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