I sure hope somebody understand this quirky behavior. We have two 2-year old cats from the same litter. Furby (female) and Gizmo (male). Gizmo is driving us nutty. He licks paper: newspaper, files, mail, kleenex, etc. He'll lick the ink off, or holes right through. He loves to chew the Kleenex from the dispenser. In the last 6-8 months, he has started licking the walls. There are grooves all over the house. Is this a behavior issue, or is Gizzie missing something in his diet?????