Murasaki is the daughter of Souju and Renjo Kuhōin. The Kuhōin family maintains a tradition that their offspring must be of pure blood. As a result, women in the Kuhōin family are in a completely submissive role and considered objects only for the purpose of breeding. They are confined in a remote area known as the Inner Sanctuary. As her dying wish, Souju pleaded to Benika to one day fulfill a wish for Murasaki. When Murasaki became seven years old, she wished to fall in love just as her mother did. She understood that her mother endured in the Inner Sanctuary because of her love for Renjo. Benika, to keep her promise to Souju, helped Murasaki escape from Inner Sanctuary and entrusted her to Shinkurō.

Although she was stubborn and snobbish, Shinkurō was quick to scold her if she did anything wrong. As a result, Murasaki quickly learned how to behave as a "commoner" and begins to trust Shinkurō. She also makes friends with the other residents at May Rain. However, after a while, Murasaki is kidnapped and taken back to Inner Sanctuary. After hearing from Benika the truth behind Inner Sanctuary, Shinkurō vows to meet Murasaki again to hear her true feelings. When confronted by Shinkurō, Murasaki reveals that she does not wish to live in Inner Sanctuary and Shinkurō proceeds to save Murasaki from her fate in the Kuhōin family.

Murasaki grows very attached to Shinkurō. Despite being only seven years old, she gets jealous when Shinkurō gets close to other girls. She has expressed her desire to marry Shinkurō. However, because she is still young, she wants to wait until she is older before she confesses her love for Shinkurō.

In the anime, Murasaki remains in Kuhoin Mansion on the condition that the entire system changes and she be given the choice to choose her partner.