JK Rowling gave Harry Potter fans some material for their nightmares when she revealed that before plumbing was installed in Hogwarts, students and teachers merely "went" on the floor and magicked away their waste.
Rowling shared this disconcerting truth in a post on Pottermore, the website she uses to communicate with her fans. It was part of a larger anecdote on the 'Chamber of Secrets,' after which one of the Harry Potter books is named, but no one really paid attention to the rest.
Posted for National Trivia Day, the tidbit inspired more questions than it answered (and it's doubtful whether anyone was really asking the questions it answered).
As usual when "It's magic!" is invoked as an explanation, there were some logical flaws in the setup.
A few pointed out that indoor bathrooms have been around for quite a bit longer than Rowling thinks – indeed, even the most primitive medieval setups had some kind of privy room, even if it was just a hole in the floor that led outside the castle walls.
Others saw the tweet as the logical outgrowth of Potter fans' desire for ever more salacious trivia – and Rowling's willingness to feed that hunger.
But most people were just grossed out.