Sounds like OCD. I guess cats can get this too - but why - and how the heck to break them of it??? Maybe Franklin is just bored. Have you tried toys or other distractions with him?

Many years ago when I wore my hair long, I had a cat who insisted on sucking on it and biting on it. The only way to stop him was to remove either myself or the cat. It took him a long while, but he finally got the message and eventually stopped.