Standing before Subaru is someone he never expected. The truth of the attacker's identity leaves him bewildered, and he feels everything crumbling around him as he dies yet again. Then, for the fourth time, he awakes on his first day at the Roswaal mansion. This time, the night of the fourth day passes without incident, and Subaru is stunned as he greets the morning of the fifth day... but then the situation takes an unexpected turn.

Suddenly, high school student Subaru Natsuki has been summoned to another world on the way back from the convenience store. With the biggest crisis of his life being summoned to another world, and with no sign of the one who summoned him, things become even worse when he is attacked. But when he is saved by a mysterious, silver-haired girl with a fairy cat, Subaru cooperates with her to return the favor. When they finally manage to get a clue, Subaru and the girl are attacked and killed by someone. Subaru then awakens in the place he was summoned and notices he gained the ability "Returns by Death" and has become a helpless boy that only has the ability to rewind time by dying. Beyond the despair, can he save the girl from the fate of death?