Zombie apocalypse survivor Aoki leads a lonely life until one day, he encounters a very peculiar zombie wearing his former school's uniform. He finds that instead of attacking him, she simply stares back at him and can even speak his name. However, as she cannot say much more, Aoki passes the encounter off as quaint and leaves her behind. But he soon realizes that this zombie has unclear motives when she persistently follows him and even protects him from other mindless flesh-eaters.

As Aoki decides to stay together with the zombie, she soon becomes his dear and irreplaceable companion. But in a world where man and zombie are in constant and vicious turmoil, can the two really coexist?