Mia is the youngest elf of Boruenean Forest and the daughter of Laya (Lamisauya) and Lia (Lilinatoa). Though she is a member of Satou's party, Pendragon, she doesn't become one officially until she returns to Boruenan Forest after Satou saved her from Zen and makes the decision to stay by his side when he's to leave the town with the approval of her parents. (Source: Death March Wikia)