Mary-Joe is a bit of a nympho and not all that bright. She is the daughter of trog leader, Billy-Bob, and she is currently working for Dusty as a prostitute. However, Mary-Joe does not think of herself as a prostitute. She thinks that men are just real nice-like and give her and Dusty money as a gift. The sex part is just a fun bonus. She is very approachable as she spends most of her time in Dusty's Desires flirting with the men, and occasionally women that swing that way.
If the Prisoner 'buys some time' with Mary-Joe, she will become impregnated. Around three game months later the Prisoner will randomly encounter bounty hunters, if he chooses not to investigate why they are hunting for him, he will begin randomly encountering trogs. After nine months it revealed that Billy-Bob put a bounty out on the Prisoner for avoiding his responsibilities to Mary-Joe. If the Prisoner can't talk his way out, Billy-Bob will have to be killed.
If the Prisoner tells Billy-Bob that Mary-Joe is actually a prostitute he will lead the trogs into a violent conflict in Downtown, Dusty's Desires will close down and any remaining trogs will leave Hoover Dam.