She told fans Monday what she thinks happened to many of the book's characters after the final installment.
In a 90-minute live Web chat, she fielded some of the approximately 120,000 questions submitted by devotees. It was her first public comment since "Harry Potter and the Deathly Hallows" -- the last book in the series -- debuted on July 21.
Rowling said she was elated to share with fans the secrets she'd been harboring since she conjured up the idea for the boy wizard during a train journey across England in 1990.
"It is great to be able to do this at last," she said. "I've looked forward to it for so long!"
"Deathly Hallows" sold over 10 million copies in its first weekend. All seven books in the blockbuster series have sold a combined 335 million copies worldwide.
In the novel -- which centers on Harry's journey to kill Lord Voldemort, the most powerful dark wizard of all time -- the young wizard learns of three powerful magical objects called the Deathly Hallows that, when combined, will make their owner the Master of Death, meaning he or she accepts mortality without fear.
Rowling said in the online chat the hallows were in part inspired by "The Pardoner's Tale," one of Chaucer's "Canterbury Tales" about greed and death.
Rowling shared with fans, many of whom said they'd read the final book several times in the last week, where she imagines their favorite characters went after the series' conclusion.
SPOILER ALERT: Those who do not wish to know what happens to the characters after the book ends should stop reading here.
Rowling said the world was a sunnier, happier place after the seventh book and the death of Voldemort.
Harry Potter, who always voiced a desire to become an Auror, or someone who fights dark wizards, was named head of the Auror Department under the new wizarding government headed by his friend and ally, Kingsley Shacklebolt.
His wife, Ginny Weasley, stuck with her athletic career, playing for the Holyhead Harpies, the all-female Quidditch team. Eventually, Ginny left the team to raise their three children -- James, Albus and Lily -- while writing as the senior Quidditch correspondent for the wizarding newspaper, the Daily Prophet.
Harry's best friend Ron Weasley joined his brother, George, as a partner at their successful joke shop, Weasley's Wizard Wheezes. Hermione Granger, Ron's wife and the third person of the series' dark wizard fighting trio, furthered the rights of subjugated creatures, such as house elves, in the Department for the Regulation and Control of Magical Creatures before joining the magical law enforcement squad. The couple had two children -- Rose and Hugo.
Luna Lovegood, Harry's airily distracted friend with a love for imaginary animals who joins the fight against Voldemort in the Order of the Phoenix, becomes a famous wizarding naturalist who eventually marries the grandson of Newt Scamander, author of "Fantastic Beasts and Where to Find Them."
And what Muggle, or non-wizard, song would have been played at the funeral of Albus Dumbledore, the most brilliant and talented wizard the world had ever known?
"Surely 'I Did It My Way' by Frank Sinatra," Rowling told her fans, referring to the song "My Way," written by Paul Anka but popularized by Sinatra, among other singers.
As the chat wrapped up, Rowling thanked readers for their loyalty to the series.
"What can I say? Thank you so much for sticking with me, and with Harry, for so long. You have made this an incredible journey for Harry's author."