Mio Yuzunogi is a student council president at a high-level school for both study and sports.
Her childhood friend Rinka Ayukawa, her cousin Yui Ikoma, and her junior student association, Konomi Asahina, who loves her, are having a
busy and enjoyable day.
Her parents are mainly active overseas, so they are rarely in her house, but she
wasn’t lonely because she had a helper, Rabbit Yasushi, who lived there.
She had a family-like relationship with Shiori, as she thought of each other as sisters.
Mio is having a fulfilling day.
However, one day, her unexpected misfortune fell on her.