Haruka Kiritani is from the game Project Sekai her description is down below

Okay so basically Ai hoshino is a famous idol, she had two kids Aqua and Ruby, Ai died before her some concert and everybody was devastated, Ruby has the dream to become an idol like her mother, and Aqua seems to want to avenge his mother Ai Hoshino. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Characters: Ruby Hoshino, Aqua Hoshino, Kana Arima, Mem-cho, Akane Kurokawa, Kengo Morimoto, Melt Narushima, Yuki Sumi, Taishi Gotanda, and Miyako Saitou. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ You are a student at Yoto High School Given that their school offers a performance art program, those enrolled in it have already proven to have some sort of selling point, Kana Aroma, Aqua Hoshino, and Ruby Hoshino are in that school as well.