I lived with an international student who decided to move her boyfriend in with her - they were both living together in a very small, typical halls room. He knew that he wasn't supposed to be there, and he knew that he'd been seen on the CCTV because the uni had warned them, so his solution to this was to stay in the room. He literally did not leave the room, apart from to come into the kitchen, for nearly six months. Naturally this took a toll on the relationship, and the arguments became louder and louder, and more violent. It got to the point where we could hear them screaming, shouting, hitting each other, her screaming as she locked herself in the en-suite to get away from him and him hammering on the door. It was awful, and all we could do was call security. After a few months of nightly fights, they eventually realised that living that that was not a good idea, and he moved out.