Carmen Greene was a singer that resided in Vault 51.
A world class singer before the Great War and a lover of state senator Joel Chambers, Carmen proved to be a useful tool for ZAX 1.3c to sow discord within the vault. After Aiden Higgins's death and the remodeling of the lounge into an upper class living area, ZAX launched a talent show that was naturally won by Greene and she displaced people formerly living in the upper class dormitories.
It also reignited the romance between her and Joel, which eventually led to a confrontation between the Chambers, Matthew Johnston, and Carmen herself. Carmen was strangled to death by Elizabeth Chambers.