Maron is a 16-year-old high school student who appears ordinary but is exceptionally talented in gymnastics. Her alter-ego is Kaitou Jeanne, the reincarnation of Jeanne D'Arc. With the help of Finn, an angel sent by God, she embarks on a mission to seal away demons that have come to Earth to steal the beauty from human hearts. These demons hide inside beautiful objects, usually pieces of art, and are captured when Jeanne hits them with a pushpin and shouts "Checkmate!", transforming them into chess pieces. Despite her warm smile, Maron hides her loneliness and true feelings.
Her parents left her at a young age to work overseas and have not contacted her since. The first call she receives from her mother informs her of their decision to get a divorce. Consequently, Maron lives alone but finds solace in the family of her best friend and neighbor, Miyako. Initially, Maron dislikes Chiaki, but as they grow closer throughout the series, she falls in love with him. In the manga, she marries Chiaki, and they have a daughter named Natsuki, who is either the reborn form of Finn or the past life of Finn.
