I have no idea what this thing is that is growing on my cat. He's a boy almost 6 years. I just notic

I have no idea, but bumping this up, in hopes someone will be along soon that can help.  Is this new? Is he limping, or seem to be in pain?

Doesn't look like an abscess, more like a growth, but,   I would make an appointment w/ the vet to get it checked out soon.

Hi, You need to get him into a vet and have that removed and have a histopathology done on it ASAP. I don't know what it is but it looks like it could be a tumor of some sort that while small and insignificant looking now can suddenly become a serious life ending situation for a cat spreading to the lymph nodes etc. Please get it removed as quick as possible to avoid the spread of it if it is a tumor. Which it does look like.

I knew an 8 year old spayed female cat that had this tiny little bump under her eye. The owner didn't have the money to remove. The vet did a cytology by needle aspirate of the lump. Within 3 months had to put her to sleep because the tumor grew so fast and went into the lymph nodes etc. Removal would have involved the entire eye and half of her face. That is how much it grew by the time the report came back. It was an adenocarcinoma. So please don't make the same mistakes. Get it off of him now. Even if you can't do the biopsy right now get it removed. They can always hold the sample for you to send in later.