Usually seen smiling, Maria is one of the central characters of the series. Two years ago during the events of 428: Shibuya Scramble, she was abducted by Snake terrorists and they infected her with the Ua virus to force her father, Kenji Ōsawa, to make them a cure to the Ua virus to save her life. While her life was saved thanks to her father's anti-virus, the trauma she endured during the Shibuya incident made her suffer amnesia. As a result, she cannot remember certain events during that incident, including not remembering having met Alphard before. Prior to the Shibuya incident, she befriended Canaan after being saved from hoodlums during a trip somewhere in the Middle East. As her dream is to become a photographer, she became the partner of Minoru Minorikawa before the pair's assignment in Shanghai and her subsequent reuniting with Canaan. Several characters have made fun of her cowlick hairstyle and her relatively small bust size.