Welcome to Pet Talk! My cat Yodie, a tortie, had something similar in her right eye that I didn't even notice. She was being checked at my vet's as a follow-up visit for ear polyp surgery when my vet spotted it. I can't recall the name of what it was but it required salve in her eye after the vet scraped it. It took several visits before it finally cleared up. Good luck and please keep us updated.

ETA: Ok, I realized that the info I gave you was hardly any info at all, so I looked up Yodie's receipt and she was treated for a corneal ulcer and an immune mediated condition similar to pannus. Pannus is a non-painful inflammatory disease of the cornea and conjunctiva, which usually is limited to dogs, especially German Shepherds. Yodie later rubbed her eye on the edge of furniture because it was clearly bothering her but I think that was because of the eye salve. If your cat should have this disease, though, it's important that you get it treated because it can eventually cause blindness if left untreated and treatment is a life long commitment. Fortunately, Yodie's condition was similar to pannus but was not pannus. I hope this helps but didn't scare you.