The old-fashioned pure cafe "Moa", which is loved by the locals, had another face called the detective agency. "More" was opened by the current owner, Michiru, the mother of Yumihiko, and Michiru has solved various problems as a detective. After Michiru's death, her brother Goro and her son Yumihiko took over the store, and the detective business was contracted by a part-timer Monaco, which was once helped by Michiru. One day, Monaco, who was consulted by the mother of the luxury club "Sun" about a malicious customer, successfully solves the case with an intelligent arrangement, but the client stops the opportunity and the situation gradually becomes complicated and serious.