She is friends with Yoriko Kusumoto. She sees Yoriko as her reincarnation.
She was then pushed by Yoriko at the train station and severely injured.
Later, she is revealed to be involved in an experiment where her head is put into a small box where she is somehow still alive for at least a few days after being taken away by Amemiya (who is in love with her).
Her mother is Yuzuki Yoko (who at first claimed to be her sister). She is the result of the incest relationship between Yoko and her father, Mimasaka Koushirou.