Harry Potter creator JK Rowling says she will never write a fantasy novel again or allow another author to continue the series about the adolescent wizard.
"I will make sure that no stranger ever writes Harry Potter books," the best-selling author told German newspapers sold on the streets by the homeless.
"Harry Potter is mine," the 42-year-old said in an interview coinciding with the launch of the German version of the seventh and final book in the series -- "Harry Potter and the Deathly Hallows".
"I'm the only one who understands him," she said, adding it was a mistake to think that any half-ways talented author could write a sequel to a famous work.
Rowling admitted that it had not been easily writing the final Harry Potter book.
"Particularly gruelling was the day on which I wrote the 35th chapter, the one in which Harry prepares for his death. All the emotions that had stored up inside me after years of writing about Harry suddenly poured out," she said.
Rowling admitted that on a few occasions she found it hard going during that time but had never resorted to creative assistance from others.
"Even if someone had proposed a better end for Harry Potter, I could not have used it because it would not have been my ending," she said.
Rowling, who spent a decade writing about the Hogwarts School pupil, said she had often been asked whether she would now turn her attention to books for adults.
"But I've already done that with Harry Potter," she said. "The books have been read by many, many adults. But if I think of something that will work just for adults, then I will write about that as well."
Asked whether the final Potter book with lots of killings made it suitable for young children, she replied: "I know what you mean, and it filled me with unease to hear that Harry Potter is read aloud to five-year-olds. They should be at least seven."
It was the second time that Rowling has helped German newspapers sold on the streets by the homeless and socially deprived.
The last time was four years ago when she allowed them to publish the first chapter of "Harry Potter and the Order of the Phoenix" before it hit the shops.
Rowling herself lived off social security in Britain before making her breakthrough in 1997 with "Harry Potter and the Philosopher's Stone".
Some three million copies of the German version of the last Harry Potter novel have been printed in time for its launch on Saturday. The English version topped the German best-seller list when it was released in July.