If you watch long enough, under certain conditions, shadows grow impatient. When in a room alone with a small light source, focus on it.
The shadow will slowly close in on you, until you move. Of course, it is afraid of the light, as dark cannot snuff out light, but light can indeed destroy the dark. Watch sometime in a room with only internal light. If you stare at them for long enough, the shadows will begin to move. Sometimes you can make out shapes.
These things have lived with you your whole life, and will follow you wherever you may go, unless you command them in the proper authority to leave. Ensuring they have no legal right to be there.
Few know and understand the proper authority, and even fewer know just what to do.
The shadows are always watching.