You remember the knife on your bedside table, left over from the snack you had earlier. You lunge for it, and throw it into the darkness.
An earsplitting scream fills the room, seeming to come from everywhere at once. You can't think, all you can do is wait for it to stop. You wonder if it's going to go on forever.
It stops. According to your clock, less than a minute has passed. You get no more sleep that night.
You never see anything resembling eyes in shadows again. You stare at the corner of your room every night as you lie awake, replaying the scream in your mind.
End.