A girl who is training to become a doctor she serves as an Engineer in Lanseal Academy's Class G.A native of the city of Yuell, Cosette was orphaned during the last Imperial invasion of Gallia when her parents were killed in front of her eyes. Heavily traumatized by the blood of her family covering her, Cosette became colorblind and developed a severe case of hematophobia or fear of blood. After the war's end, Cosette enrolled at the Lanseal Military Academy to become a doctor like her father