Koharu Kusumi from the Japanese idol girl group Morning Musume made her solo singing and acting debut as the main character, Kirari Tsukishima; portraying the character both in the anime and in a real-world context made her one of the pioneers of the "idol voice actor" crossover beginning in the late 2000s.
[3] From June to September 2007,[4] Mai Hagiwara from Cute was cast as the anime-original character, Hikaru Mizuki, and became part of the in-show idol subunit Kira Pika with Kusumi; Hagiwara would also make live television appearances portraying the character[5] and appeared as a special guest during Kirarin Revolution's final concert event on May 4, 2009.
[6] The second season, Kirarin Revolution Stage 3, cast Sayaka Kitahara and You Kikkawa from Hello Pro Egg as the anime-original characters Noel Yukino and Kobeni Hanasaki, who form the in-show Japanese idol group MilkyWay with Kirari.
[7] Takuya Ide and Shikou Kanai were cast as the new voice actors for Hiroto Kazama and Seiji Hiwatari, the members of the in-show group Ships.
[8] Like Kusumi, MilkyWay and Ships released music and made appearances at concerts and other television shows, such as Haromoni and Oha Suta, as their characters.