A travelling doctor stationed in Diamond City, who seems to spend most of her time tending to the clients Doctor Sun is too busy complaining about to help. Marie was formerly a singer from Goodneighbour until a man pretending to be a doctor extorted her late mother for caps under the guise of using them to buy more medicine--now she dedicates her life to being a doctor and providing accessible and affordable healthcare to the people of the Commonwealth. On her travels, she is constantly looking for the man who killed her mother, determined to kill him herself for taking her mother away; she also occasionally visits the Valentine Detective Agency to see if they've found any information since her last visit. The answer thus far has always been "no."

Marie has a bright but loud and sarcastic attitude and cares greatly for the safety and well-being of the people around her, doing all she can to ensure their safety and health. However, she is short-tempered and is almost guaranteed to be found scolding individuals who are reckless with their health or personal safety (it's almost always Basil). She gets tired easily as well, whether that's because of going days without sleeping or a chronic fatigue. Surprisingly does not get along with other people easily outside of work.

When she isn't working, she still likes to sing.