Before it was demolished and a brand new music centre was built, the music lessons at Marling School were held in a shit building, called Grafton House.
One room in Grafton House that contained only a comfortable chair. A spectacular design feature of this room was that the door could only be opened from the outside.
So, rumours flew around that this room was where the music teacher kept his stash of mind-blowing pornography. If you thought you had seen sex, then this pornography would put you right, by blowing your mind.
The imaginations of normal children in this situation stretches to a writhing black shape, with a compelling question mark on top. So once a child had become so curious as to go inside, he would be locked inside, forever*, with only a comfortable chair to sit on, and his imagination to wank with.
*Not forever.