Harry Potter author JK Rowling says she will miss writing the series when she finishes work on the final novel.
JK Rowling was making her first US appearance for six years
"I will go through a mourning period, then I will have to think of something else to write," the 41-year-old author told an audience in New York.
However, she said writing the final book was "fun in a way it hasn't been before" because "the pressure is off".
Rowling read extracts from the most recent Potter novel at a charity event organised by author Stephen King.
The benefit performance, which also featured World According To Garp novelist John Irving, was held at New York's Radio City Music Hall.
Money was being raised for Doctors Without Borders and The Haven Foundation, which helps artists who are unable to support themselves after falling ill.
It was Rowling's first US appearance for six years. The author told the audience she had been unwilling to take long flights with two young children.
King said he was looking forward to reading the next Potter novel, while Irving added: "I have my fingers crossed for Harry."
"I don't want him to go over the Reichenbach Falls," said King - referring to Sir Arthur Conan Doyle's attempt to kill off Sherlock Holmes in the novel The Final Problem.
Sir Arthur later resurrected the character after being deluged with letters of protest from fans.
Helena Bonham Carter will take a role in the new Harry Potter film
Rowling has said two characters will perish in the final Harry Potter novel, but told her New York audience she was not looking forward to writing their deaths.
"I didn't enjoy killing the character at the end of book six," she said, "but I had been planning that for years, so it wasn't quite as poignant as you'd imagine.
"I'd already done my grieving when I actually came to write it."
As Rowling completes the last Harry Potter book, filming has begun on the fifth instalment of the movie franchise.
Helena Bonham Carter has been announced as the latest addition to the all-star cast for Harry Potter and the Order of The Phoenix.
The actress, who last appeared in Charlie and The Chocolate Factory, will play the evil Bellatrix Lestrange in the film, which is due out next year.
Film studio Warner Brothers has already announced that Imelda Staunton will play dark arts teacher Dolores Umbridge in the film.