Beijing ? Hong Ying knew she was courting trouble when she wrote a novel about adultery set in 1930s China, with explicit sex and characters based on real people.

The author of “K: The Art of Love” says she sought permission from the family of a British poet depicted having an affair with a married Chinese poet. But the London-based writer didn’t take that step for other characters.

Now her book, already in print in Britain and elsewhere, is banned in her Chinese homeland and a court has ordered her to apologize publicly.

Though China often bans books it considers obscene or subversive, the impetus of this order was unusual: It came from a lawsuit by a British woman who says “K” insulted her late parents, both literary stars of prewar China.

Hong Ying denies harming anyone. The author, whose full name is Chen Hongying, says she will refuse the court’s order to apologize and plans to appeal.

The case pits artistic audacity against Chinese heritage in a society where it isn’t unusual for authors to base fiction on real people and courts are only beginning to hear pioneering lawsuits over claims of defamation.

It draws on tradition-minded Chinese law that allows lawsuits to defend a dead relative.

Chinese have been filing such lawsuits since the 1980s, said C. Stephen Hsu, an expert in comparative law at Beijing’s University of Politics and Law. Even works of fiction are open to challenge, he says, if characters are recognizable.

“It’s rooted in Chinese culture,” he said. “Even though your parents are deceased, you still have an interest in protecting their reputation because yours is tied with theirs.”

Hong Ying said she based “K” on letters and journals by Julian Bell, a nephew of novelist Virginia Woolf. Bell taught in China and was killed in 1937 in Spain’s civil war. In the novel, Bell has an affair with a poet named Lin, who teaches him the secrets of classic Chinese books on sexual technique.

The lawsuit was filed by Chen Xiaoying, who says the Lin character is based on her mother, a poet named Ling Shuha who had an affair with Bell and died in 1990.

Hong Ying denies that Ling Shuha is Lin, who she says is an amalgam of women from Bell’s writing. But Chen says she recognizes places, dates and events from her mother’s life.

Chen, 67, a translator and broadcaster in Britain, doesn’t object to scholars studying her mother’s affair but rejects “K” as pornography and says it smeared her name.

When the original Chinese version of “K” was published in Taiwan in 2001, Chen says, friends there contacted her to say they recognized her parents.

“I couldn’t finish reading it. It was too upsetting for words,” Chen said.