UPDATE 10/01/15:

Following a widespread misunderstanding that HBO had issued the document in question, the network released a statement to Variety firmly placing the burden on Central Casting. The statement, excerpted below, came shortly before SAG-AFTRA notified members that they have the right to "withdraw from scenes" on the set of Westworld:

The document that the background actors were given was created by an outside extras casting vendor. It was not requested, written or approved by HBO, Warner Bros. Television, or the producers, and contains situations that we do not require of any actor. We are rectifying immediately the discrepancies in this vendor’s document with our actual on-set practices, which provide a professional and comfortable working environment for all performers.

This is some of the best advertising the world has ever seen.

See original story from 09/30/15 below.

If HBO's Game of Thrones has taught us anything (it's taught us quite a bit), it's that unfettered nudity is kind of awesome. Free from the restraints of traditional television networks, the home of alternative bible Curb Your Enthusiasm has never shied away from pushing the envelope or at least setting the envelope on fire because there are no rules on HBO. With that distinction firmly in mind, HBO's recent requests of extras working on the set of the forthcoming Westworld is actually just really good advertising.

Westworld extras are having to sign consent forms agreeing to participate in "graphic sexual situations" including (but presumably not limited to) "genital-to-genital touching" and "posing on all fours while others who are fully nude ride on your back," according to Deadline. The extras are reportedly being paid as much as $600 for the shoot, a price no doubt ballooned by the strenuous nudity requirements of the material. The full consent agreement, given to an unknown number of potential extras by Central Casting, reads like the greatest ad campaign of all time:

This document serves to inform you that this project will require you to be fully nude and/or witness others fully nude and
participate in graphic sexual situations. By accepting this Project assignment, you may be required to do any of the following: appear fully nude; wear a pubic hair patch; perform genital-to-genital touching; have your genitals painted; simulate oral sex with hand-to-genital touching; contort to form a table-like shape while being fully nude; pose on all fours while others who are fully nude ride on your back; ride on someone’s back while you are both fully nude; and other assorted acts the Project may require. The Project will also include language and sexual situations that some may consider personally objectionable or uncomfortable.

The futuristic "dark odyssey" series, featuring a producer cosign from current god of Star Wars J.J. Abrams, stars Anthony Hopkins, Ed Harris, Evan Rachel Wood, and James Marsden. Though it's not expected to debut until 2016, HBO did release a quick teaser back in August:

Unconfirmed sources have also obtained this exclusive on-set image, featuring one of Westworld's most buzzed-about scenes in progress: