found out if Mister Square's was the killer and Discovered the darkness story by picking up tracks that make's him speak and try to find out who the killer was
you will have too many choice's pick up one and see how Mr.Square interact with it, some of the tracks will make Mr.Square mad.
to know if he's mad? keep your eye on the "DANGER BAR" or he will move (at least he will move he's head).
you will not be able to stop him, but if he move's from the chair you can start a music that make him calm down.