In a world shaken by an unusual pig disease, college student Kai Yuzuriha finds herself in the midst of a terrifying zombie outbreak, struggling to survive alongside her friends in a school infested with the undead. With 100 days until help arrives, the once-familiar school has transformed into a zombie zone, challenging their friendships and pushing their courage to the limits. Can Kai and her friends endure the 100 days, or will the relentless zombies dwindle their numbers day by day? In this race against time, they fight to navigate the chaotic apocalypse that has upended their world.