You're curious about the call and the meaning behind it. The most direct approach to solving the riddle seems to be doing exactly what you were warned not to do, so you head to the nearest aperture and look out. It's a normal sunny day, and you can see your neighbor's home, a tree, the street, all looking very normal. You grasp the bottom of the window and slide it up. As the window rises, so does the image you had been seeing through it...or painted on it? But now you can see through the opening, and the true image behind is...nothing? You can see only raw darkness... Slowly, the darkness begins to flood into the room, englufing everything and consuming you, until all that is left of you and your home is...darkness.