In China, pornography is illegal both online and offline. The penalties vary according to the level of offense, says Wang, an official at the National Office Against Pornographic and Illegal Publications, who declined to give his full name.

As part of a crackdown on cyber pornography, the government launched "Cleaning the Web 2014" campaign in April. Since then it received more than 30,000 complaints, according to Wang, who works in the information section of the department.

"The Interests of the underage consumers is well considered here," Wang tells China Daily of the focus on protecting children.

The office, with 27 members from other ministries, is set at the State Administration of Press, Publication, Radio, Film and Television. An arm of the administration identifies pornographic material online and in print.

"Actually it is easy to detect porn because that's the information free of any artistic or scientific value," Wang says. "Average readers can do that."

The officials tasked with identifying such material need to classify it, too, because the most serious violations are taken as cases in criminal courts, while lighter offenses attract administrative punishments.

The identification is mainly based on Article 367 of the Chinese Criminal Law and two of its interpretations by the Supreme People's Court and Supreme People's Procuratorate respectively in 2004 and 2010, as well as the Regulation Identifying Lewd and Pornographic Publications by the SAPPRFT.

There are detailed rules, including those that involve sex with children or of the same sex, sexual violence and other depictions that a common reader or viewer may find disturbing. The office is open to offense reporting 24 hours a day and is present on the social media platform WeChat.

Pornographic content, among Web literature, accounts for a small portion online when compared to videos and other such elements. There could be 10 books in a hundred that are offensive, he says. But mostly underage people read literature on the Web, and online "lit porn" easily gets millions of hits, Wang adds.

Li Xiaoliang, veteran web editor of Chuangshi Literature under Tencent, says their readers are aged between 16 and 40. "The majority of the readers love to read fantasy that fulfills their dreams, but not the sexual content," Li says.

Readers have their own standards by which they judge books. Many love books with good plots and positive values, according to Wu Wenhui, CEO of Tencent Literature.