For detached high schooler Kaito Hoshino, the world is just background noise—until a classmate vanishes from reality. Suddenly, Kaito is the only one who remembers the boy ever existed, leaving him isolated in a world with a glitch in its memory. His desperate search for answers leads him to Yuki Amasawa, a mysterious girl who claims she was also erased, and a terrifying glimpse of a faceless monster that wears his own reflection.