[Dueller]

Talked to my vet brother who looked at pic...that is just a wad of nasty compacted hair or possibbly an old Qtip cotton wedged in between its teeth.... Pull it out with tweezers with a little tug or scrape with your fingernail...imagine a wad of popcorn hulls stuck between your tooth and gums. Should come right out. Needs its teeth cleaned. Also looks like it has gingivitis. Kind of an older cat likely. May be a a rotten or broken tooth undeneath but unlikely if its not in distress.