Kaolinite, known as Kaori Night in the manga and Kaorinite in the English anime, is a loyal assistant to Professor Tomoe and harbors deep feelings for him. She makes her first appearance in Act 24 of the manga and Episode 90 of the anime.
A notable difference between the two versions is Kaolinite's treatment of Hotaru. In the anime, Kaori often provokes and mocks Hotaru, whereas in the manga, she shows genuine concern for the girl. However, Hotaru feels that Kaori's presence in their home signifies that she does not know her place.
Kaolinite exhibits various powers throughout the series, such as levitation, teleportation, limited shape-shifting, and using her hair as a weapon, similar to Mistress 9.
In the anime, she is the first of the Death Busters to openly attack individuals possessing pure heart crystals, utilizing bio-engineered Daimons she helped create. Her goal is to find the three Talismans, which are unknowingly possessed by Sailors Uranus, Neptune, and Pluto. Sailor Mars, Sailor Mercury, and Sailor Jupiter all become targets of her monsters. In episode 102, she discovers the brightness of Sailor Moon’s Pure Heart Crystal and pursues it. The Sailor Senshi unite against her, leading to her defeat by Sailor Uranus, whose "World Shaking" attack causes her glass-based attack to backfire, encasing her in a pillar of glass and causing her to fall from the Tokyo Tower. In episode 113, she reappears as Hotaru Tomoe’s guardian, calling herself Kaori (except in the dub, where she remains Kaorinite). It is later revealed that Professor Tomoe revived her. However, she feels overshadowed by the Witches 5 and is jealous of them and Hotaru. By episode 123, filled with hatred, she steals the Pure Heart of Sailor Chibi Moon, Hotaru’s best friend. The crystal is ingested by Hotaru’s possessed form, awakening Mistress 9, the Messiah of Silence. Kaolinite’s last words are congratulations from Professor Tomoe before being thrown into an electrified wall by Mistress 9 for "having served her purpose."
In the manga, Kaolinite's role differs slightly. Unlike the anime, where her origins are unknown, it is revealed in one of Professor Tomoe’s flashbacks that she became Kaolinite after being struck by lightning during a chaotic storm while they attempted to reconstruct his daughter Hotaru’s maimed body. When she rises, her eyes are glowing. Her title is "Magus Kaolinite," a position the Witches 5 aspire to reach. As a Magus, she has access to the Tau Star System’s crystal. In the manga, it is Kaolinite, not Tomoe, who commands the Witches 5. She views them solely as servants, showing annoyance when Mimete seeks her help. It is implied she wishes to be Pharaoh 90’s partner instead of Mistress 9, a desire Mistress 9 finds amusing. When Mistress 9 awakens, she orders Kaolinite to eliminate the Sailor Senshi. Kaolinite subdues the Guardian Senshi but is ultimately defeated by Uranus, Neptune, and Pluto. Reunited, the Senshi confront Kaolinite in the President’s office of Infinity Academy, where she transforms into a Daimon and is destroyed by Super Sailor Moon’s "Rainbow Moon Heartache" attack.
