Ruby is a prostitute born in Carbon and the first to greet the Initiate on arrival.
Ruby is available for sexual encounters (for 10 caps) and asks the player to help her find her cat, Mr. Pussy. Mr. Pussy can be found, however he will be found dead, having been killed by monsters in the Crater. The Initiate can bring his corpse back to Ruby for caps and XP.
Later in the game, her locket is stolen by raiders attacking the town. Ruby asks the Initiate to retrieve it during his attack on the raiders' base, the Mill. She claims to know Harold who traveled through the town some time ago.
Ruby also gives the quest to kill drunken raiders, where the Initiate has to kill 10 raiders in the Carbon Bar.
- Depending on the Initiate's gender and race, she will give a different speech after paying for her services. She will vomit if the main character is Cain. She must be informed that he is a ghoul for her to understand it, but telling her this will not prevent the player from further wasting money on her services.
Ruby appears only in Fallout: Brotherhood of Steel.