Tsukiuta.

Tsukiuta. (ツキウタ., lit. "Monthly Song") is a running music and original audio drama CD series which features a collaboration between seiyuu (voice actors/actresses) and Vocaloid music producers, themed on the individual months of the year. From their first CD release in December 2012, the series has expanded to include more than 70 (music and audio drama) CD releases, a smartphone game, a dance live in 2016, and an anime adaptation set to air Summer 2016. Fujiwara (from Movic) is credited as the original creator of the series, with original character designs by Jiku.

Plot
The Tsukiuta. series revolves around a set of 24 main characters. For every month in the year, there are two representatives, one male and one female, accompanied with an assigned producer. The characters are further divided into four different units: two all-male units (Six Gravity and (Procellarum), and two all-female units (Fluna and Seleas). The male characters are from Earth, and are currently working as idols signed under the in-series talent agency, Tsukino Talent Production. The female characters inhabit a society on the Moon (a society not known by many), and are studying to become entities called Goddesses, and are also under Tsukino Talent Production.

Official

 * Tsukiuta. Series: Official Website
 * Official Twitter Accounts
 * Official Twitter Account (@tsukiuta1)
 * Simpler Official Twitter Account (@tsukiuta2)
 * Tsukiuta SS Official Twitter Account (@tsukiutass)
 * Tsukiuta. Radio Official Twitter Account (@tsukiutaradio)
 * Tsukiuta. THE ANIMATION (anime adaptation): Official Website, Official Twitter Account (@tsukiani_info)
 * Tsukiuta. STAGE (dance live/stage adaptation): Official Website, Official Twitter Account (@tsukista)
 * Tsukino Talent Production: Official Website
 * Tsukino Park (smartphone game): Official Website, Official Twitter Account (@tsukino_park)

Other Sources

 * Tsukiuta. THE ANIMATION on MyAnimeList
 * Tsukiuta. THE ANIMATION on AnimeNewsNetwork