My roommate and I both have a cat. They're two 9 month old males who get along very well. However, their personalities are wildly different. My cat would lay around all day if he could while her cat always seems to be jumping off the walls. We each have a litter box in our rooms for our cats, but her cat seems to only want to use the one in my room while my cat has never used the one in her room. Her cat will come into my room and break things, rip my clothes, knock everything down, and then hide under my bed so I can't get to him. I've tossed him from my room multiple times but he just does not seem to understand. I've tried to only keep my door cracked some, but the little guy always seems to sneak through when I'm not looking. I can't keep my door shut at all times because I wouldn't want to keep my own cat confined, and I wouldn't want her to shut her cat in her room all day either.. but he's an absolute nightmare! How can I get him to understand boundaries??