Career
Together, they make up the sub-unit Queen & Elizabeth. On November 10, 2012, it was announced she would be making her solo debut. On November 25, Kasai performed her solo song for the first time, the title announced as "Masaka" (まさか).
lieutenant was released on December 26.
On December 17, Kasai announced that she would leave the group. Her farewell ceremony was on May 3, 2013.
Team K 1st Stage: Hoshi no Ondo (星の温度)
Team K 2nd Stage: Kinjirareta Futari (禁じられた2人)
Team K 2nd Stage: Fushidara na Natsu (ふしだらな夏)
Team K 3rd Stage: Maria
Himawari Gumi 1st Stage: Idol Nante Yobanaide (アイドルなんて呼ばないで)
Himawari Gumi 2nd Stage: Tonari no Banana (となりのバナナ)
Team K 4th Stage: Oshibe to Meshibe to Yoru no Chouchou (おしべとめしべと夜の蝶々)
Team K 5th Stage: Dakishimeraretara (抱きしめられたら)
Team B 5th Stage: Candy (キャンディー)
Team A 2nd Stage: Nageki no Figure (嘆きのフィギュア) (May 28, 2005, replacing Atsuko Maeda).