"Once someone introduces you into the club as a worker, nobody cares about who you are and what you do there. It's a very open space," he says.

Fang says it was also interesting that the young women looking for work would first ask to be the DJ or waitress, but after about two weeks, she will talk to the "Daddy" or "Mommy" (the leader of the sex workers) and ask to be a xiaojie, a female sex worker.

"Because that is the right thing to do at such clubs, like college teachers trying to become professors in their milieu," Fang says.

The research that he did for his PhD thesis is now playing an important role in the new program Fang, now a well-known Chinese sexologist and professor at Beijing Forestry University, is working on - Ending gender-based violence: men and boys in action!

Fang said he always identifies himself with the marginalized, and he traces the reason for this back to his childhood. When Fang was 3, his father, an athlete, committed suicide; as a fatherless boy, Fang was often sneered at and bullied at school. Now that he has grown up, he says he always tries to speak up for the "weak" and for their rights.

In 1993, when Fang was working as a journalist at Tianjin Workers Daily, he came across a brief news report about a homosexual forum in Beijing. At that time, homosexuality was a forbidden topic. The forum was held in the name of the prevention of AIDS. But the media reports provoked public indignation and the forum was stopped.