TSUKIUTA.

''“"Tsukiuta." is a project by the original characters on the theme of 12 months.'' Please enjoy the story decorated with music and voice!" TSUKIUTA. (ツキウタ. lit SONG OF THE MOON or MONTHLY SONG) is a unit series under the management of TSUKINO TALENT PRODUCTION and features the units Six Gravity, Procellarum, Fluna, and Seleas.

Overview
The four TSUKIUTA. groups are the first units who debuted under TSUKINO PRODUCTIONs and were the first series to have their own anime adaptation, TSUKIUTA THE ANIMATION, and stage play series, TSUKIUTA STAGE.

Similar to how the ALIVE & SQ units are themed after the four elements (fire, earth, water and wind) and the VAZZROCK members each represent a type of gemstone, the TSUKIUTA. series represents the twelve months of the year. Each month has two representatives, one from the men's side and one from the girl's side.

TSUKIUTA.'s series anniversary date, celebrating the day they debuted and officially joined TSUKINO, is December 7th. As of 2022, TSUKIUTA. has now celebrated ten years of activities.

Mascots
The TSUKIUTA units have the same mascot type; TSUKIUSAs, also known as Tsukiusa/TsukiUsa (ツキウサ). The name is a mashup of TSUKIUTA. and usagi (うさぎ) the Japanese word for rabbit; the choice of a rabbit is likely due to the multitude of legends regarding rabbits and the moon. Each monthly pair has a representative TSUKIUSA with the USAs body matching that months associated color.

Behind the Scenes
Like other series handled by TSUKINO, the TSUKIUTA. series units all share one artist: Jiku.

One of the original selling points for TSUKIUTA. as a series was the fact that each month features a different producer, with each producer being a prominent producer within the VOCALOID community. Due to scheduling conflicts and other issues, these producers are no longer the only ones responsible for the TSUKIUTA. units music. If their usual producer is not available the song is usually instead credited to Tsukino Mikoto, the in-universe president of TSUKINO PRODUCTIONs.

The twelve producers for the different months are as follows:
 * January - Machigerita
 * February - Nijihara Peperon
 * March - Yuuyu
 * April - ChouchouP
 * May - Nem
 * June - Yuyoyuppe
 * July - Hitoshizuku×Yama△
 * August - UtataP
 * September - John Zeroness
 * October - takamatt
 * November - Kikuo
 * December - Satsuki ga Tenkomori

However, as of recent years its somewhat unclear as to whether Kikuo is still considered the producer for the November pair. While no official statement has been made, he hasn't featured as a producer on any TSUKINO music since 2017, with his last release being albion ~Futari Dake no Shiro~. All subsequent music produced by the November representatives have been credited to Tsukino Mikoto.