Set within the chaotic entertainment district of Joshidaikoji in Nagoya, Japan. Hironaka Mio works as a hostess at a club in Yanagase, Gifu. She is quick-tempered and is full of justice. Her younger brother is Hironaka Daiki. He works as a private detective in Joshidaikoji. The jobs he gets usually require doing mundane things like finding missing cats. He also works part-time as a bartender. Hironaka Mio and Hironaka Daiki become involved in a serious crime case. They look for the criminal behind the crime. Adapted from the novel "Jyoshidaikoji no Meitantei" (女子大小路の名探偵) by Hata Takehiko (秦建日子).