It freaking IS! I was petrified when I found it!
I was actually doing Bjorn's route when Mikko sidetracked me and I was like "Oh what the hell, might as well play his route instead". And then you find the key and get a choice to sleep in your room, and I thought: "Well I haven't done that before, might as well see how it plays out" and five minutes later I'm looking at the title screen, my jaw on the floor.