Ok I have had a hairless male rat named Otis for about 6 months now; he has never bit anyone and is as sweet as can be. I bought him a all black furred male rat named boots. I had cleaned Otis cage with water and vinegar to eliminate his scent. I introduced the boys in my back room and they didn't seem to interested. Then about 20 minutes later is put them in a cage ( not Otis cage ) and watched.. Otis seemed to clean his neck very intensely and boots didn't move except squeak. But once Otis would bite under his neck boots would move away, I feel bad for boots I'm not sure if Otis is being mean or what? Please help right now hey are in two different cages I want them to get along please help!