A high school that has achieved zero bullying thanks to excellent teachers and a perfect monitoring system. Kiyokazu, a first-year student there, meets his former classmate Shijo, who was bullied in middle school. The two gradually connect with each other at this bully-free school. But one day, Kiyokazu finds out that Shijo was being bullied. And she jumps off the roof. A shocking "zero bullying" mystery!!