Japanese: コーアン
Romanji: Kōan
Aliases: Koan Kurozuki
Residency: Nemesis, Tokyo (in the anime, she lives there after being purified by the Silver Crystal)

Member of the Ayakashi Sisters
Cosmetic saleswoman (after being purified in the anime)


Petz, Calaveras, Berthier (sisters)




Black Moon Clan

Gender: Female
Species: Nemesis humanoid
Human (after being purified in the anime)
First Appearance
Manga: Act 15 - Infiltration, Sailor Mars
Anime: An Angel? A Devil? Mysterious Girl From the Sky
Anime Voiced By: Wakana Yamazaki (Japanese)
Alice Poon (DiC English dub, episodes 54-57)
Mary Long (DiC English dub, 58-65, 79)
Eden Riegel (Viz Media English dub)

Koan is the youngest of the Ayakashi Sisters who accompanied Rubeus to 20th Century Tokyo in order to look for Chibiusa and the Silver Crystal. This is the original depiction of the character created by Naoko Takeuchi.

Nomenclature & Etymology


Koan is named after Kooankou (紅安鉱), a mineral that is also known as Kermesite and Red Antimony. The "Kermes" part of Kermesite means "Crimson." The Kanji character that is missing is the character for a "mineral" or "ore." Kermesite is found in chocolate as well as other places.

Her given human name in the Japanese manga is Koan Kurozuki, with her last name meaning "black moon".

Her Dic and Tokoyopop name Catzi/Catzy could be because she has a hairstyle which resembles cat ears. Her old dub name name Catzy which could also sound like Cat could be in contrast to Berthier's dic name Birdy/Birdie, which both names indicate "cat" and "birdy".



Koan has wavy dark purple hair that falls down her back and dark purple eyes. She wears a pink pinstriped onesie, a dark purple tutu and dark purple heels. She also wears a black rose corsage around her neck and an identical ring on her right hand.



Koan first appeared in Act 15 of the manga, where she was in charge of Operation 001: Operation Recruit. Disguising herself as a T*A Academy for Girls student named Koan Kurozuki, she recruited people to the Black Moon by foreseeing their deaths and then promising a peaceful passing if they joined her. Unfortunately, those who agreed bore a crescent sign that would then spontaneously combust, as they were most likely unable to handle the power.

After finding one of the school's teachers who had suffered this fate, Sailor Mars confronted her, but was trapped in Koan's flame barrier. Though Sailor Moon used her new Cutie Moon Rod to destroy Koan with Moon Princess Halation, she was unable to break the flame barrier, and Sailor Mars was abducted by Rubeus.


Koan was the most conceited and most ambitious of the Spectre Sisters, as well as the most developed in the anime. She was constantly making up her face, bemoaning her looks, teasing her elder sister Calaveras, and shopping as a human for new cosmetics and clothes. Koan's greatest dream was to become the Queen of Crystal Tokyo - with a King Rubeus by her side. Much of this fantasy was fueled by her belief that Rubeus loved her like she loved him, a fantasy which Rubeus did nothing to discourage.

As the first sister to appear, Koan became the one most engaged in finding Chibiusa (as opposed to simply capturing Crystal Points, which she only did once). This was a job that Rubeus often trusted her with, and the more she failed, the more determined she became to kill Chibiusa and win Rubeus's love.

Koan did not have the same respect for her elder sisters as Berthier, who always referred to Calaveras and Petz as "oneesama" (御姉様; elder sister). Despite this, she seemed to truly love her determination to purify the others as well.

Koan is the first to encounter the Sailor Senshi. She attacks by shooting Dark Fire upon her enemies.

Koan encountered the Sailor Senshi four times. The first was when she tried to capture Chibiusa Tsukino for Rubeus, but was fought off by Sailor Moon using her scepter. The second time, she tried to take over a crystal point (Hikawa Shrine) with the help of her Droid, Dumble. Anyone defeated by Dumble fell under Koan's spell, but Sailor Mars defeated Koan, setting her on fire. The third time, she and her sisters Berthier, Calaveras, and Petz fought the Sailor Senshi, but were forced to retreat when Sailor Moon defeated Rubeus.

Koan fell in love with Rubeus at one point, and when he sent her on a mission to take over Rei Hino's temple again, she gave him some cologne, but he was uninterested and crushed it in his hand. Later, he said she was looking "beautiful as always", leading her to believe that he was still in love with her. While chasing after Chibiusa, Koan encountered Rei and Yuuichirou, and fought them. Yuichiro jumped in front of Rei to protect her from Koan's Dark Fire. Rei transformed into Sailor Mars. With the help of Tuxedo Mask, she defeated Koan with Burning Mandala. Rubeus appeared and dumped Koan, kicking her out of the team for failing to capture Chibiusa. Koan went on a rampage, and the Sailor Senshi attempted to fight her off, but Sailor Mars protected her from Sailor Jupiter's attack and convinced her to turn good. Sailor Moon used a new technique, Moon Crystal Power, on her to eliminate the last of the negative energy inside Koan, and from here, she opened a cosmetic shop. In anime she is kind, jealous and somehow strong.

Koan also convinced Berthier to turn good as well when she attempted to freeze herself with her power. She was later captured along with Berthier by Calaveras and Petz in an attempt to turn them evil, but they turned good in the end, and the four decided to run a cosmetic stand together.


Koan appears in Act 15, where Rubeus gives her Code 001: Operation Recruit to convert humans to their cause. She poses as a student at T*A Girls Academy, where Rei Hino attends and becomes the leader of the supernatural club, the Black Moon. Koan sets up a fortune telling booth and tells her clients about how they will die. Koan then reveals her true self and traps Sailor Mars in a flame barrier. She is killed by Sailor Moon, but Sailor Mars, is still trapped in Koan's fiery shield, after Rubeus takes her.

Sera Myu

For her background in the musicals, click here.


Koan in the fight uses the Dark Fire to create streams of fire, flaming barriers and setting fire to people and objects such as Sailor Moon's tiara. She can also use her fire to trap her opponent in a sphere of flame. 




  • She is the Ayakashi Sister equivalent to Sailor Mars.
  • In the Materials Collection, her ideal voice was described as a sexy adult-sounding voice
  • In the German translation of the manga, both Calaveras and Koan stated to be the youngest sister.
  • Koan appeared in chapter four of the video game Sailor Moon: Another Story,and she been turned evil again, along with her sisters. She was the first to attack the Senshi on the Black Moon UFO. However, instead of being healed, she was killed by the Sailor Senshi. She used the attack Dark Fire.
  • In the English dub of the first anime, Koan is the oldest of the Spectre Sisters.
  • Koan is the Spectre Sister counterpart of Sailor Mars, as both use fire-based attacks.
  • Koan is forcibly changed back to her evil self by Apsu and is a boss fight in Sailor Moon RPG Another Story. However, she like her sisters, seems to still have control of their own minds, but their bodies are forced to fight the senshi. Also, the senshi are forced to kill them. It is unknown if they were revived afterwards.
  • She is named after the mineral Kermesite, known in Japanese as "koanko." Among other places, kermesite is found in chocolate.
  • In the DiC English dub that she appears in, she speaks in a flirtatious tone. But in Episode 63 up to 76, she speaks in a Brooklyn accent but in a rougher and deeper voice due to her previous voice actress Alice Poon is replaced by Mary Long which she almost sounds like Marge Simpson


Black Moon Clan
Nega Moon Symbol

Leaders WisemanPrince Dimade
Ayakashi Sisters KoanBerthierPetzCalaveras
Droids Boule BrothersAquatici and Veneti
Other Members RubeusEsmeraudeSaphirBlack Lady

Leaders WisemanPrince Dimande
Ayakashi Sisters KoanBerthierPetzCalaveras
Droids AtsugesshoNipasuDumbleFuraikiJaamanenAvogadoraAkumudaJakokuMarzipanUderingPharmakonDogbaGiwakuBoule BrothersRyuax
Other Members RubeusEsmeraudeBlack LadySaphir

Leaders WisemanPrince Dimande
Ayakashi Sisters KoanBerthierCalaverasPetz
Droids Aquatici and VenetiHyuru Hyuru
Other Members RubeusEsmeraudeBlack LadySaphirSpotted TilmunAaronManna

Leaders WisemanPrince Dimande
Ayakashi Sisters KoanBerthierPetzCalaveras
Droids Boule BrothersAquatici and Veneti
Other Members RubeusEsmeraudeSaphirBlack Lady

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