(CNN) -- It's J.K. Rowling's first foray into fiction for adults. And thanks to her Harry Potter fame, her new novel, "The Casual Vacancy," is already a best-seller, even before its release Thursday. But some parents worry that their children might expect another adventure at the Hogwarts School of Witchcraft and Wizardry, which this book is not.
"I'm dying to read 'The Casual Vacancy,' " said Kacy Faulconer, a 40-year-old mother of four kids ages 5 through 15. "But I'll have to read it first before I decide whether my kids can read it."
Faulconer writes about books and parenting on her blog, "Every Day I Write the Book." But even if she decides to let her kids to read "The Casual Vacancy," she isn't sure they'll want to. "Frankly, even though we are huge Harry Potter fans, I'm not sure they'll be that interested since it doesn't take place at Hogwarts."
Harry Potter is certainly a tough act to follow. The seven-book series sold more than 450 million copies and spawned a multibillion-dollar film franchise.
"The Casual Vacancy" is set in an English town rocked by the death of a parish councilman. Publisher Little, Brown and Company asks in a statement, "Who will triumph in an election fraught with passion, duplicity, and unexpected revelations?"
According to reports by the select few who have actually read "The Casual Vacancy," the new book includes real-world problems such as poverty and drug addiction.
To make sure that children don't stumble into a disturbing story, Cindy Hudson, author of "Book by Book: The Complete Guide to Creating Mother-Daughter Book Clubs," suggests that parents read the novel alongside them.
"The best thing is to just pick it up and read it at the same time," Hudson said. "It gives the parents a chance to talk about some of the issues that come up."
"The Casual Vacancy" is under a strict embargo until its release. But the novel has been at or near the top of Amazon's best-selling book list for the past several weeks -- even though it doesn't come out until Thursday.
Sara Nelson, editorial director of books and Kindle e-readers at Amazon, isn't surprised. "She is a beloved author," she said. "Her books are always best-sellers."
She also points out that Rowling's fans span a range of ages. Many Harry Potter enthusiasts are adults, although the books were intended for the younger set.
And of course, many readers who were children when the series appeared have come of age along with Rowling's narratives. The first book in the Harry Potter saga came out more than 10 years ago. Many who hopped on board the Hogwarts Express for the first time in the late 1990s are now old enough to drive -- and handle adult themes in the books they read.
"I think a lot of her audience has grown up," said Christina DiRusso, a 23-year-old from the New York area who reckons she first happened upon Harry Potter at the age of 9. She has read every book in the series and seen every movie. While she was growing up, she even shared them with her four younger siblings.
DiRusso says she might read "The Casual Vacancy" because of Rowling's name: "I'm a huge fan of hers."
Barnes & Noble is counting on that fan loyalty. Bookstores have been heralding the arrival of "The Casual Vacancy" for several months. Signs featuring Rowling's picture advertise the book's release date and offer pre-sales.
Patricia Bostelman, vice president of marketing for Barnes and Noble, said, "The book is being positioned in our stores as one of the major books through the fall and the holidays."
"The Casual Vacancy" display will be found at the front of stores -- away from the children's section.