Harry Potter: 10 Times JK Rowling Admitted To Changing Her Plans
9. There Was Going To Be A Vampire Teacher
Many readers nursed in some cases a hope and in others a suspicion that perhaps Professor Snape would be revealed as a vampire. He certainly seemed the type, with his black cloak and sweeping movements. It is however not up until book six, The Half-Blood Prince, that a fully-formed vampire is first seen in the enigmatic guest Sanguini at Horace Slughorn's party.
While Snape was never meant to be the one, Rowling admits that she did have plans for a vampire teacher at Hogwarts. In early notes, as revealed on Pottermore, there was the undead Professor Trocar. Like many Potter characters, his name carried a revealing meaning - a trocar is a sharply pointed tool used to penetrate arteries and body cavities. He never was given a subject, and was dropped from the plans early on, but it certainly would have been interesting to have gotten to know vampires better in the Potterverse.
Perhaps there wasn't room for more than one black-cloaked, sinister dungeon-dweller on the staff.