|Relative||Kagamiin Kyōka (daughter)|
|Manga Debut||Chapter 11|
Ryōko is a tall, attractive woman and is about the same height as her daughter. She has blonde hair and a figure that mirrors her daughter's.
Ryōko has a very flirtatious personality and likes to tease her daughter. She seems to have formed a liking toward Rintaro and would like to see him hook up with Kyōka. She is normally seen in an elaborate kimono.
Nihon Buyou: As a member of the Kagamiin family, she is an expert on the Japanese Traditional Dance, as she judged her daughter's and her partner's performance during the Bakugyaku Festival.
Stealth Skills: She seems to have some skills in stealth as she was able to sneak up on her daughter and Rintaro in the family bathhouse.