メリー

Chart Style: Arcade (Extreme) "Around and around in the Merry Go Round of Love!"

Also known as: Merii, Merry

Composed/Arranged by: Funta
Lyrics by: yura
Vocals: Haruka Amami (CV. Nakamura Eriko), Chihaya Kisaragi (CV. Imai Asami), Yayoi Takatsuki (CV. Nigo Mayako), Makoto Kikuchi (CV. Hirata Hiromi), Miki Hoshii (CV. Hasegawa Akiko)
Vocals (alt ver.): Shiho Kitazawa (CV. Amamiya Sora), Kana Yabuki (CV. Kido Ibuki)

This is a song from the CD THE iDOLM@STER Christmas for you!, originally released in 2007.
The MV is from it's later debut in THE iDOLM@STER Million Live! Theater Days.
Pictured in the song background is official iDOLM@STER art featuring the 5 characters, presumably scanned from an artbook.
An alternate video is included, specially a duet version of the song by Shihko Kitazawa and Kana Yubuki of the same series. I would probably tinker with your offset if you use this version.