@HaltingBlooperWorse Case: It could be caused be infection or could be a ruptured ear drum
Best Case: Ear Mites (the ears will kind of have a black coating on the inside as if they look dirty)
The vet will give antibiotics for an infection.
If is a ruptured ear drum than you hella need to get the cat to the vet
If it is Mites than the vet will give you ear drops for the cat.