The old school closed due to black mould spores but really the ancient caretaker had been found murdered in the attic. His blood and other stuff leaking through the ceiling and walls, causing a rotting meat stink. He had been a pervert, taking boys to the attic under the pretence of showing them wonderful things then having his way with them, so it was good he was finally gone.
(Inspired from; https://only100words.xyz/2017/06/29/three-line-tales-week-74/ with thanks.)
The Story Files 