Adopted cat 3 years old no 'papers'

Hello! My boyfriend and I adopted a cat from a co-worker of mine. Now the thing is she adopted the cat when he was a kitten but never got any papers with it cuz it was a friends nest. She did castrate him and gave him his shots etc. But we have no idea if he actually is a breed or not? It's not that important, we're just a bit curious

Probably a domestic, longhair domestic (possibly medium-hair, I dont see the tail properly)

I dont see sure traces of especial Ancestry.

Sweet boy!

Thanks StefanZ!