Sailor Chibichibimoon Cast List
Chibichibi wasn't featured in very many musicals, but did lend her cuteness to a handful of shows! Here are the actresses who played her:

Kawasaki Mao
Kawasaki Mao as Sailor ChibiChibimoon and Out of Costume Profile:
First Name: Mao
Last Name: Kawasaki
Birth date: November 13, 1986
Birthplace: Osaka, Japan
Height: 5'2" [158cm]
Blood Type: A
Good With: Reading, Bass Guitar, Guitar.
# of Myu Performances: 49 (as Chibichibi)

More Information:
Mao Kawasaki- Anime News Network, Kawasaki Mao at Wiki.theppn

Kawasaki was the longest running Chibichibi, but that wasn't her first experience in SeraMyu. She also portrayed Chibiusa in a few earlier productions. After playing both the chibi parts, she later came back to myu to play Black Lady.

Following her multiple roles in Sera Myu, she played Shan-In "Glass Heart" Lee in the Angel Heart TV series. She also played Sakura Kasugano in Street Fighter Alpha: Generations. Accordingly, she has worked to promote both with appearances, CD singles, etc.

Musicals in (as ChibiChibi):
Eien Densetsu
Eien Densetsu Final Act [kaiteiban], Final First Stage

Asuke Mikiko
Asuke Mikiko Out of Costume and as Sailor Chibichibimoon Profile:
First Name: Mikiko
Last Name: Asuke
Birth date: October 20, 1988
Birthplace:
Height: 5'2" [159cm]
Blood Type:
Good With:
# of Myu Performances: 41

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More Information:
Asuke Mikiko at the Database of Commercial Message [Japanese]

Mikiko played Chibichibi in one musical only, Shin Densetsu Kourin- Beginning of the New Legend.

I haven't found any information on Mikiko following myu. Aside from the (agency?) profile I found, there hasn't been anything else. And her official website has either changed links 3+ times, or is offline completely.

Musicals in:
Shin Densetsu Kourin BEGINNING OF THE NEW LEGEND

Gochou Yuka
Gochou Yuka as Sailor Chibichibi and Out of Costume Profile:
First Name: Yuka
Last Name: Gochou
Nicknames: Yuka, Okayu Birth date: July 19, 1993
Blood Type: B
Good With: Singing, Acting, Parallel Bars
# of Myu Performances: 40 (as Chibichibi)

More Information:
N/A

She played Chibichibi in one musical, Summer Starlights * Ryuusei Densetsu. She also played Chibimoon in a few productions.

Musicals in (as Chibichibi):
Starlights*Ryuusei Densetsu

Horita Mina
Horita Mina Out of Costume and as Sailor Chibichibimoon Profile:
First Name: Mina
Last Name: Horita
Birth date: November 22, 1994
Height: 4'1" [124cm]
Blood Type:O
Good With: Dance, Acting, Basketball
# of Myu Performances: 21 (as Chibichibi)

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More Information:
Horita Mina at Wiki.thePPN

Mina played Chibichibi in 2003 and 2004, for the musical Kakyuu-Ouhi Kourin The Second Stage Final, as well as the fan kansha event for that musical. Prior to playing Chibichibi, she played Chibiusa in Starlights * Ryuusei Densetsu in 2003.

Following Sera Myu, it is unknown what Mina did.

Musicals in (as Chibichibi):
Kakyuu-ouhi Kourin