LONDON — After months of hype and anticipation, J.K. Rowling’s first novel for adults has appeared, swept into the arms of hopeful booksellers and an army of grown-up Harry Potter fans eager to find out what his creator has done next.

A gritty and darkly humorous tale of ugly realities in a pretty English village, “The Casual Vacancy” seems a long way from the Hogwarts School of Witchcraft and Wizardry, and reviewers gave it a mixed reception. But Rowling said Thursday she wasn’t worried about the response.

“I’ve had my books burnt,” said the author, whose magical stories were condemned as Satanist by some Christian groups.

A story of ambition, envy and rivalry, the novel recounts the civic warfare sparked in the fictional Pagford when the unexpected death of a town official leaves a vacancy on the governing body. Characters set on a collision course range from the affluent lawyer Miles Mollison to the Weedons, a ramshackle clan living in The Fields, the run-down housing project on the edge of town.

Rowling told a 1,000-strong audience at London’s Southbank Centre that the idea for the book — “Local election sabotaged by teenagers, basically” — came to her on a plane several years ago.

Writing for a more adult readership, she said, had been “freeing” — though “in other senses it’s a challenging book,” told from multiple viewpoints.

Rowling said the book’s focus on teenagers, the heart of Pagford and of the novel, was not a million miles from her previous work — although these troubled and profane youngsters are “not Harry, Ron and Hermione.”

“They are very different teenagers,” Rowling said. “They are contemporary teenagers.”

The book’s sex and swearing have drawn the most comment so far — some audience members were startled to hear the F-word pass Rowling’s lips during Thursday’s reading. But the presence of death is perhaps the book’s most adult element, and one that loomed over Harry Potter’s world, too.