Sankaku is going to graduate from junior high soon, and she is a girl who treats many things with cold cynicism because of a disappointing romance during elementary school. She now does not have the courage to love and decides to bury her feelings for her long-time crush, Yokosuka, and graduate without telling him about how she feels. One day, she happens to run into Yokosuka and his friends, plotting to do something stupid on graduation day. Soon, Sankaku is caught in their crazy plan!