A new Halloween-related Harry Potter story by J.K Rowling will be published online today. Credit: PA In what is most definitely a treat for Harry Potter fans, author J.K. Rowling will post a brand new Halloween-themed story online today. The 1700-word story, to be published on Pottermore.com, focuses on Hogwarts professor and former witch Dolores Umbridge, who first appeared in Harry Potter and the Order of the Phoenix. Umbridge, who featured as the Senior Undersecretary to the Minister for Magic, is not only one of the most malicious Potter characters, she is the only person other than Lord Voldemort to leave a permanent physical scar on Harry. Do you agree with @jk_rowling that Bellatrix Lestrange and Dolores Umbridge are as bad as each other? pic.twitter.com/reRFBt7YJC — Pottermore (@pottermore) October 29, 2014 The world-famous novelist announced earlier this month that she had written a new story as a Halloween surprise for fans. The website has be...