A high-school girl and the protagonist at the beginning of the story who discovers she is a descendant of a tennyo named "Ceres" and is Ceres' latest medium for existence. The Mikage family takes this as a threat and continuously tries to take Aya's life. Her father is killed attempting to protect her. Her mother is forced into a coma for the majority of the series. While Aya is initially horrified that her life has been turned upside down, she is determined to right the past doings of her family and recover Ceres' hagoromo so that her family will no longer suffer in fear of her. As the series progresses, she falls in love with Toya and they conceive a child together.