"He's just an old man."
"He's just lonely."
"Let's just be nice to him."
— Letting your guard down is where hell begins.

From the author of Murder Addiction comes a spine-chilling psychological thriller.

Praise is pouring in: "An absolute page-turner you won't be able to put down!"

Kowarin Tomoyasu is a 26-year-old office worker who grew up in a peaceful home, having never known true fear in her life. But one day, her tranquil world is shattered. A mysterious elderly man suddenly appears at the apartment she shares with her boyfriend, launching a campaign of relentless harassment. Her boyfriend cowers in an unnaturally terrified state, while the local police brush her complaints aside. Meanwhile, across Tokyo, another young couple is viciously attacked by an old man. The husband is brutally slaughtered in an act of extreme violence, and the wife is abducted.

Detective Sho Sasaka, a crime-obsessed investigator who joined the force after her sister was murdered during her childhood, teams up with Terumi Kitanoya—an eccentric yet brilliant detective from the Tokyo Metropolitan Police Department’s First Investigation Division—to track down the missing woman.

As they unravel a trail of baffling crimes committed by an old man, what shocking truth awaits them at the end? A bone-chilling psychological suspense that will leave you breathless.