When fourteen-year-old Dazai Osamu is sent on a routine assignment by Mori Ōgai, he expects weapons, information, or perhaps a new recruit. Instead, he finds a silent girl his own age being sold to the Port Mafia. Beautiful, frail, and bound in enough chains to restrain a monster, she never speaks and barely reacts to the world around her. Yet the fear in her captors’ eyes tells Dazai everything he needs to know—there is something dangerous hidden beneath her empty stare, and Mori has paid a fortune to make it belong to the Port Mafia.