**"You don't need math for murder" - Miharu S.** Raizou Hiraga is a retired officer from the Tokyo Metropolitan Police Department. After learning that his grandson is stricken with a deadly illness requiring expensive treatment, Raizou comes across a vacancy flier for the mysterious SS Agency and applies for the job. However, after taking his first job with 11-year-old Miharu Suzukaze as partner, he discovers that his new occupation is more than meets the eye…