Kamei was selected from the Morning Musume Love Audition 2002 to join Morning Musume as a member of the sixth generation. She first appeared on the single "Shabondama" and her first album was Ai no Dai 6 Kan.
Towards late 2004, Kamei is thought to have opened up after receiving her own segment on the Japanese variety show Hello! Morning, where she had been a regular since her debut. In the segment, known as "Eric Kamezō no Maido Arii!" (エリック亀造の毎度ありぃ!?), she, along with her co-host Yuko Nakazawa, and most often several guests promote the latest products from the Hello! Project. Her segment was removed from the show in the winter of 2005, but she still stars in the rest of the show as a regular.