As website operators scrambled to delete or modify online material that contains sexual content in line with a new crackdown by the authorities, the owner of a fiction website struggled to determine what to delete and what to keep.

Huang Zhiqiang, the founder of Panda Reader, a well-known fiction website which also provides mobile literature services, could not help asking questions like: Would describing kisses before sex be counted as porn?

There should be clear standards for sexual material, or else all grown-ups will be stuck reading children's books, said Huang.

His worries came after the National Office Against Pornographic and Illegal Publications announced on Sunday that China would launch a new round of campaign against the spread of all sexual content on the Internet - whether it is text, columns, articles, videos or images - from mid-April to November.

The campaign, dubbed "Cleaning the Web 2014," will conduct thorough checks on websites, search engines, mobile application stores, Internet TV, USB sticks and set-top boxes.

"Porn does great harm to minors and the social ethos," said a circular about the campaign.

Websites, telecom operators and Web portals were asked to conduct self-examination immediately and clean up information and links, it added.

As a result, commercial websites started to cut porn related advertisements and news portals moved stories with possible sexual connotations to inconspicuous positions. Social networking sites such as Sina Weibo blocked a series of accounts which posted sexual images or words, or contact details of prostitutes.

But for fiction in particular, as Huang points out, it is impossible to cut all sexual content.

A clean cut

According to the circular, all online text, pictures, videos and advertisements with sexual content will be deleted and those websites, channels and columns found to produce or spread sexual information will be shut down or have their administrative licenses revoked.

By Tuesday more than 20 fiction websites like the Sina Book had conducted self-examinations and shut themselves down to "rectify" their content, the Xinhua Daily reported Tuesday.

More cases will be published later, Wang Qiang, the media officer of the national anti-porn office, told the Global Times.

Many pieces of online fiction tend to highlight sexual content in order to attract more readers and make a profit, and such moral virtue campaigns can help reduce the number of sexual novels and change people's views about online literature, Huang said.

However, without a clear standard, some "clean" work may also be implicated and discourage the authors.

Zhao Bili, a writer contracted by qidian.com, a famous Chinese novel website, said that two of her popular novels on homosexual love were removed from the website.

Zhao said her novels only contained a very small and brief part depicting the sex between two men. "But the editor still grouped it to the porn ones, since the homosexual topic is quite sensitive."

"This self-censorship will only lead to a larger amount being cut than necessary," Huang admitted. "There is a red line in the authorities' mind, but website editors have no clue where it is."

As a fiction writer himself, he suggests his colleagues follow the rule: "The work is OK when you'd like to show it to your kid."

The 'invisible' red line

An anonymous source from the national anti-porn office said their standard of distinguishing between art and porn is based on how it is depicted.

"If the descriptions were written in an artistic way, then they are not porn. Explicit details of people's reproductive organs, harmful sexual habits and violent or abusive depictions of sex are never tolerated," the source said. "Few gay stories are encouraged."

Those standards can bend from time to time. They are taught and shared as experience inside the office, she told the Global Times. If the contents are too barefaced and disseminated widely, the case will be handed over to the police department, which will review it again.

The Chinese Criminal Law stipulates that those who committed the crime of dissemination of pornographic materials could be sentenced to up to two years of imprisonment.

But in regard to online stories, a judicial interpretation released in 2013 said that only when the dissemination scale is large enough will one be held guilty.

Returning like weeds

Similar nationwide online campaigns took place in 2011 and 2013, and there are smaller local campaigns every year in different places. Authorities across the country captured 205.3 million illegal publications last year alone.

The current campaign is in response to the persistent spread of pornography online despite multiple previous campaigns, said the media officer of the national anti-porn office. "Parents are among the most concerned groups in regard to those pornographic ads, sites and novels."

"But no matter how many times you cut them, they will just grow back like weeds," said Li Gang, a news editor of ifeng.com, the reading channel of which was suspended for two days after the circular.

These days, it is cheap and easy to start a porn site. Many operators can abandon their sites and come back later without fear. Many commercial websites love those ads because they increase network traffic.

Fang Liyong, an Internet expert, said such ads should be cracked down on consistently.

For "porn novels," such campaigns also seem to have limited effects.

Xie Shouquan (pseudonym), a part-time online writer, said that in most of the cases, sexual pictures and words can be filtered by software, but videos and novels often need to be checked one by one by human hands.

This kind of keyword filtering can work for commercial websites, news sites, social networking sites and forums, but it cannot work for thousands of novels online. "In Chinese literature, you can change the word 'bed' or 'sex' to so many other alternatives without changing its meaning, so porn stories will exist even under such campaigns," he said.

Cutting all sexual things online does not solve any problems and erotic marketing is effective because everyone has sexual needs and curiosity, and as adults, self-discipline is much more effective than supervision by the government, said Fang.