She was first sent by Tomoe to implant Daimon pods in objects to turn them into Daimon Heart Snatchers, who would then extract Pure Hearts from people. She was searching for three Pure Hearts in particular that would turn into a mirror, a saber, and a crystal ball once extracted, but she never did find them. After her latest Daimon, Senishenta, was defeated, Kaorinite absorbed Senishenta's power from the shoe she created her from, and fought the Sailor Scouts. She was winning until Sailor Uranus used World Shaking on her, freezing her in her own crystal beam and sending her falling over the edge of Tokyo Tower to her death.
She was later revived by Doctor Tomoe, however she never took on any assignments after this, and became Hotaru's guardian, as Hotaru was possessed by Mistress 9. The Witches 5, patricularly Byruit, disliked that Kaorinite didn't go on any more assignments, so she eventually captured Rini for Mistress 9, who ate her Pure Heart and awakened in her true form. She then struck Kaorinite with lightning, throwing her into an electric barrier and killing her. Her body disintegrated afterwards.
Kaorinite attacks by wrapping her hair around her enemies. She can also shoot a crystal beam to freeze things in crystal, once absorbing the power from the shoe she created Senishenta from.