When I was younger, I used to believe that a evil man would come in our back door at night and run around the house checking the rooms to see if anyone was there. So I always listened for my parents to go to bed (because the man would only come in if no one was up, obviously) and then I would hide under my covers and pillows completely, except for a little breathing hole, so that when the evil man looked in the room he would think that it was empty and leave. I was always terrified that one day I was going to wake up too early and that he was going to be looking in the room, and then he would laugh in a high-pitched voice (I was sure he had a high-pitched voice somehow), stuff me in a sack, and then take me through the woods to the funeral home that we live near. I always thought that was where dead people came from - they forgot to hide under the covers when the evil man came into their house!
A childhood belief about monsters

others believed things like this
- i didn't beleive this, but a kid my sister knew thought if he screamed in a really high voice, he ran faster.Anon
- I used to think the old BBC logo that was on one of my videos as a child was evil and wanted me to be dead.— tanukibear
- I used to think an evil spirit type thing called Wango lived in my dog. I was terrified of that dog.— Franklin
- I thought that "heck" was a less horrible version of hell for people who were only KIND OF evil.— Oizys
- i used to believe that bald people were evilAnon
- I used to believe that the sky was full of dead people and I would see them if I went high enough— Maria