The pinnacle of adolescence is marked by the high school graduation ceremony, where Itsuki, the older twin, relished his moment surrounded by close friends and a loving girlfriend, while Haruka suffered a dismal experience on the isolated rooftop. Yet, destiny intervened when both twins stumble off the roof and find themselves transported back to the start of their high school chapter. In a surprising turn of events, their former "best" and "worst" moments became wholly inverted.