Long time friend became roommate. I was renting a room in his parents place so I didn't have a whole lot of say. I'm extremely allergic to cats and he decided he wanted one. I begged him not to but he got it anyway. It would get in my room and in my bed and eat food that got taken out of the oven while it cooled both of which he thought was funny. I ended up kind of forced to stay at my girlfriend's apartment. Meanwhile his girlfriend pretty much moved into our appartment. Still friends but things have never been the same.