JK Rowling's personal copy of the first Harry Potter book, complete with handwritten notes which reveal the author invented the fictional sport of Quidditch after a row with her then-boyfriend, is going up for sale.
Rowling will auction a hand signed, annotated first edition of Harry Potter and the Philosopher's Stone, containing insights into how she wrote it.
The book, to be sold by Sotheby's to benefit literacy charity English PEN, contains a note on Quidditch, which Rowling said "infuriated" men, 'The Telegraph' reported.
The 47-year-old author said she designed the game in a Manchester hotel room after an argument with her then-boyfriend.
The sport is now one of the most famous elements of the Harry Potter books, played with broomsticks, hoop goals, and a flying ball with wings.
"[Quidditch] was invented in a small hotel in Manchester after a row with my then boyfriend," she has written alongside the text.
"I had been pondering the things that hold a society together, cause it to congregate and signify its particular character and knew I needed a sport. It infuriates men which is quite satisfying given my state of mind when I invented it," she wrote.
As well as writing over 43 pages of her "second thoughts" upon reading the book again, she has also included 22 ink illustrations.
Intended to show the characters as Rowling envisioned them, the hand drawn pictures include one of a baby Harry Potter sleeping on the Dursleys' doorstep and an Albus Dumbledore chocolate frog card.
Others show a "brooding" Snape, the Mirror of Erised, Norbert the Norwegian Ridgeback dragon, and a man with two faces.
The book is one of 50 first editions to be sold at the auction, and annotated by their authors.
"This can undoubtedly be regarded as the definitive copy of any Harry Potter book," Dr Philip Errington, director of printed books and manuscripts at Sotheby's, said.
"Not only is it a fine copy of a first edition of the first book, but the author has significantly personalised it with numerous written comments and many impressive and evocative illustrations," Errington said.
