For the past 15 years, Fuyukawa Misaki has lived a quiet, reclusive life while keeping her secret well-hidden. With just two months left before the statute of limitations on the murder of her colleague expires, a mysterious man appears in Misaki’s life, who says, “I know your secret.” Is he a friend or foe? The nameless man who claims to know about Misaki’s past does not reveal any personal information about himself, but only says he wants to live with her in exchange for keeping her secret. Hence, a bizarre living arrangement begins. Who is this man and what is his purpose? Meanwhile, conventional detective Kiba is convinced that Misaki is the elusive criminal behind the 15-year old murder case and is determined to uncover evidence to prove his theory. As this peculiar love-suspense drama unfolds, you will need to piece together information to solve the mysterious puzzle of murder while the clock counts down to the expiration deadline.