A childhood belief about around the house

I used to have a big bookcase in my room, and whenever I heard a noise that I couldn't explain (air conditioning kicking in, etc.) , I thought that it came from behind that bookcase. Eventually I realized that there was a man behind my bookcase who was as flat as a pancake that tried to lure me out with his weird noises. Even when we moved, I imagined that a mover guy was trapped behind the bookcase and became the new Pancake Man. I was terrified of the Pancake Man until my mom decided to paint my room and moved the bookcase away from the wall. When I asked her where the Pancake Man was she gave me weirdest look and asked me what I meant. I'm still afraid to look behind bookcases...