Not a good idea. You'd do well to let your presence be known. If anyone bitches at you, bitch right back. *At an intensified degree.* Look - how the fuck were you supposed to know 'HE' didn't have the key? You ain't no keeper of your roommate. Or - did he NOTIFY you at advance? *Like I don't have my key for now. don't lock it - sort. My roomie used to do that.* - from what I see, He apparently did NOT do so. You have every right to bitch at him. Let him know you can bitch - he won't bitch at you next time. =)