Kyouko is Tooru's mother.

When she was young, Kyouko caused trouble and cut classes, and was disowned by her parents following a gang fight. She hated her family, as her father felt she wasn't needed in the world and her mother only cared about the appearance of the family. She was also the leader of an all-female suicide gang. In this she was called "The Red Butterfly," the name originating from the legend of how the tail lights on her motorcycle danced like a bright red butterfly when she rode at night. However, Kyouko later moved on and got a job.

At some point, Kyouko fell in love with a student teacher named Katsuya Honda, which contributed to her leaving her gang. After she was beaten by her gang and disowned by her parents, he stood up for her and proposed to her. They shortly married and had a daughter, Tooru. Katsuya became a positive influence in her life, and they worked through