Oscar has had this on her vent for a while now. I’m not sure if it is a shed or something else. Since it’s been on her for a while and other parts of her have shed it is starting to worry me a bit.
Hi there....yes it's just a stubborn piece of shed. Totally harmless + will come off eventually. Many people are concerned about yellow fungus [ and rightly so since it is very serious + can often be deadly ] but Y.F is generally darker yellow, brown or even black in areas. Some pics here , you can see the big difference :