What Was in the Job Description?

Koko, the female sign-language communicating gorilla, has a breast fetish that has led to some labour strife within the Gorilla Foundation, which is charged with her care.

Two fired caretakers for Koko, the world-famous sign-language-speaking gorilla, have sued their former bosses, claiming they were pressured to expose their breasts as a way of bonding with the 300-pound simian. ...

They were threatened that if they "did not indulge Koko's nipple fetish, their employment with the Gorilla Foundation would suffer," the lawsuit alleged.

The lawsuit claims that on one occasion [Francine "Penny" Patterson, the longtime trainer of the well-known gorilla], said, "'Koko, you see my nipples all the time. You are probably bored with my nipples. You need to see new nipples.'"

Other working condition complaints are also listed by the plaintiffs.

This case sounds like a classic contract situation: to what did the parties agree? what is implied in the contract? and do the terms of the contract violate any laws?

If Patterson really did say that, she sounds a little wacko to me, "wacko" being a well-defined economics term for someone who has a utility function with arguments and weights quite different from mine.
[thanks to the many readers who have sent this to me, including JC and BF]