Marina Kuroki (黒木マリナ), full name Marina Kuroki Hayashi, now known as Mariina, born September 26, 1988, in Tokyo, Japan, was the fourth actress to play Usagi Tsukino/Sailor Moon in the Sailor Moon musicals. Her first musical was the 2001 Tanjou! Ankoku no Princess Black Lady, when she was only 12, and her final show was Shin Kaguya Shima Densetsu (Kaiteiban) - Marinamoon Final in 2005, when she was 16 years old. Although she had previously participated in the Fan Kansha event for Tanjou! Ankoku no Princess Black Lady and then the musical itself, her first Myu-related solo performance was of "An Evil Dream" during the Fan Kansha for its revision.
Marina was the second longest running Sailor Moon, the fourteenth longest running performer in Sera Myu history, and the youngest ever to play Sailor Moon. She was given the nickname "Wan-chan" (ワンちゃん; meaning "Puppy") at the 10th Anniversary Festival show by Anza Ohyama.
Marina has released several idol DVDs and appeared on a few Japanese TV programs, as well as doing several stage shows. After graduating from her role in the Myu, she proceeded to perform the openings for the anime series Onegai My Melody ~Kuru Kuru Shuffle!~ and Onegai My Melody Sukkiri♪.
- Marina's mother, Mayumi Kuroki, was also a teen idol in the 1970s.
- Marina's father, Yatsuhiro Hayashi, is a former baseball player.
- Marina's birthday is on the same day as Mizuki Sano (former Tuxedo Mask) and Nao Inada (former Sailor Venus).
Marina performed as Usagi Tsukino/Sailor Moon in the following musicals:
- Tanjou! Ankoku no Princess Black Lady
- Tanjou! Ankoku no Princess Black Lady (Kaiteiban) - Wakusei Nemesis no Nazo
- 10th Anniversary Festival - Ai no Sanctuary
- Mugen Gakuen - Mistress Labyrinth
- Mugen Gakuen - Mistress Labyrinth (Kaiteiban)
- Starlights - Ryuusei Densetsu
- Kakyuu-Ouhi Kourin - The Second Stage Final
- Shin Kaguya Shima Densetsu
- Shin Kaguya Shima Densetsu (Kaiteiban) - Marinamoon Final
- Marina was the only Sailor Moon actress who did not have any of the other Sailor Senshi actresses remain through her entire duration in that role.
- Marina's family name is the same as that of Mio Kuroki, a villain from the live-action series.