Chika Midarezaki

Formerly known as Senko Himemiya, she is Yuuka's biological sister and the last person to join the Midarezaki family. She was the former "Solitary Doll" before Yuuka was born. After Yuuka became the next "Solitary Doll," Chika tortured her in various ways and paid her classmates to bully her. She later remembers her promise with Ginichi Kizakura, now Ginka Midarezaki, and regrets her wrongdoings. Although she does not have Enka's DNA, Kyouka's ability makes her a member of the Peaceful Family Operation.