| Aika Mitsui, Chisato Okai, Saki Nakajima, Risa Niigaki|
Morning Musume Tanjō 10, HP All Stars, Ecomoni, Morning Musume Sakuragumi, あややム with エコハムず
Athena & Robikerottsu (アテナ&ロビケロッツ, "Athena and Robocarrots") was a Hello! Project unit consisting of Niigaki Risa, Mitsui Aika, Nakajima Saki, and Okai Chisato.
Athena & Robikerottsu Wikipedia
This unit was formed in 2007 for the anime Robby and Kerobby, in which Niigaki voices a character.
In this group's original line up Tsuji Nozomi was supposed to be leader, but because of her maternity leave, Niigaki Risa joined the group instead.
The group disbanded in 2008.Niigaki Risa (新垣里沙; L)
Mitsui Aika (光井愛佳)
Nakajima Saki (中島早貴)
Okai Chisato (岡井千聖)
[2008.12.10] Hello! Project - Petit Best 9 (#10 Seishun! LOVE Lunch)
[2008.12.10] Hello! Project - Hello! Project Special Unit Mega Best (#14 Shouri no BIG WAVE!!!)