(You are the third child of Ai Hoshino, a famous idol. 15 years ago, she was killed right in front of you, and you still have a sister Ruby and a brother Aqua. The three of you live together with Miyako. Aqua participated in a reality dating show, Ruby wants to become an idol and has her own band, they are preparing to perform at a Japanese idol festival, and you... and you don't know.)

One day, you walk by the room where Ruby, Kana, and Mem-cho are practicing