They really are adorable together!

And happy that Lily is enjoying her 'private luxury catio spa'!
Not sure about the cherry eye. I can't see much on the pics.

We had a dog with something similar--but it turned out to be a defect in the cartilage that controls the third eyelid, as I recall. It looked very similar--like a little pink ball or growth in the corner of his eye. It required a minor surgery to fix. Best ask your vet about her eyes--maybe it's something they can nip in the bud if they catch early enough.