A rare item hunter, meaning she collects anything with the word "Rare" in its description. She seems to have an odd sense of smell that goes off around rare items, though she will not tolerate hackers who create their own rare items, as then she would not be a "true" rare hunter. She is Mistral's (from the .hack games) 4-year-old daughter in real life; a child prodigy with an IQ of 200. Her avatar is her mother's, with a name change. Her class type is Wavemaster, "sub-class" Rare Hunter. She calls herself, "The Rare Item Hunter of Love and Justice". In every anime episode, she says the phrase "rare item" at least once. Being obsessed therewith, Mireille sometimes has a covetuous eye on the Twilight Bracelet. It should be noted that she shares the name of one of the protagonists of the Noir, also produced by Bee Train.

Her name in real life is Mirei.