Apparently John Normans "Gor" series from the 1960's has also spawned a sex-cult. There are some estimated 25,000 followers worldwide and even a splinter-group called the Kaotians.
It's been described as a bizarre sex-cult by Police who raided a house in Darlington after receiving complaints that people were being held their agianst their will. The complaints came from family members and friends of those living there but the police could find no evidence of people being constrained against their will or any other illegal activity.
Police Discover Sex Slave Cult (BBC News Online; Friday 19th May 2006)