Anri and Momoka are twin sisters. Anri's style is rather plain and average, while Momoka is very flashy. Due to the timing of their birthdays around midnight, Momoka and Anri ended up in different grades in school. Momoka is in high school while Anri is still in middle school. One day Momoka comes running up to Anri, begging for a favor. She is experiencing a relationship crisis and a break-up, and she just doesn’t want to face going to school right now. She begs Anri to take her place at school for a few days.

What adventure will Anri find at high school, pretending to be her sister? There are two boys who will make her life interesting- NAGASE Kazuto, the scary guy who sits next to ‘Momoka’ in class, and Naemura, the cute class officer that Momoka likes....