I gave you that key for emergencies. You using it for a non-emergency and walk in on me using my remote-controlled vibrator with an online friend wasn't exactly what I had in mind. You interrupted me at a very crucial moment, so now I'm not only pissed that you came into the room like that, I'm frustrated for a much worse reason. This might be a really good time to cross some of the roommate boundaries and let you take control. Who knows? This could turn out to be a very good situation...