Kaori Iida
In early 2007, Niigaki was chosen to be a member of the along with Kaori Iida, Natsumi Abe, Maki Goto and Koharu Kusumi - a unit created to celebrate Morning Musume's 10th anniversary. Their first single, , was released on January 24, 2007. On June 1, 2007, Miki Fujimoto's resigned from Morning Musume, Ai Takahashi replaced Fujimoto as leader, while Risa Niigaki took Takahashi's place as sub-leader.