Shion and Sakura are twin sisters. They do everything together.
They come from a wealthy family that has established a famous private high school "Kousho Gakuen". Shion and Sakura attend this school. The elder sister, Shion has a lot of pride in herself and has a habit of looking down on people who are inferior to her.
Compared with Shion, Sakura is delicate girl. She can't do anything without her sister Shion.