Professor of porn reveals naked truth of web sex

In real life, Katrien Jacobs is a media professor at Chinese University. Online, she was 'Lizzy Kinsey - scholarly sex machine', with her personal details, including a self-snapped shot of herself naked, on Adult Friend Finder, one of the world's largest social networks for casual sex.

A US$20 a month fee was all it took for Jacobs to enter the world of online hook-ups, where the usual rules of courtship are turned on their head, and no one makes any pretence about their intentions.

What Jacobs found out during a two-year study forms part of her book, People's Pornography - Sex and Surveillance, a rare look from the ivory tower at porn in Hong Kong and the mainland, which is due to hit the bookshelves by the end of the year.

The book, an examination of sex culture and civil liberties, also covers the sex blogosphere, youth attitudes to porn in Hong Kong, and the Chinese obsession with cosplay, where people dress as their favourite Japanese animation characters.

The Adult Friend Finder community is swelling fast, with 160,000 members in Hong Kong, up from 60,000 five years ago. In a place like Hong Kong, known for its workaholism, conservative values and computer literacy, sites like this help users on the prowl minimise their time and maximise their exposure - in all senses of the word.

It is a radical departure from conventional dating websites, where suitors try to portray their best sides, each photo or profile description subtly hinting at how funny, charming and distinguished they are.

In this world, people offer a crude, nude profile picture, and list of carnal preferences. Finding a match is not a case of reading between the lines or looking for common interests. You just bash in your preference for age, weight, height, ethnicity, and the website spits out your erotic match.