Once a year, without warning, a week disappears from everyone's life. Memories are wiped, events are erased, and no one knows why—or even remembers to ask. For most, the phenomenon is just another unexplainable part of existence. But for Ren, it’s unbearable.

He hates how people act like it’s normal, brushing off the missing time as just a minor inconvenience. Three years ago, on Recalibration Day, Ren received a mysterious notebook with the words “Don’t forget her” scrawled inside. His parents dismissed it as nonsense, but ever since that day, he’s been haunted by an unshakable feeling that he’s missing something—or someone.

Determined to uncover the truth, Ren begins an investigation into the phenomenon. As he digs deeper, he starts to notice cracks in the fabric of reality and fleeting glimpses of someone he can’t quite remember. Who is she, and why does he feel like the missing week holds the answer?