Sharaku Homonji is the eldest son of a distinguished family who has studied crime for generations. The eldest son from the Homonji family has tested for an IQ of 246 for generations and Sharaku Homonji possess an IQ of 246.
Soko Wato is a detective. One day, she is assigned to the investigation section #1. Her job there is not to investigate crimes, but to escort Sharaku.