Aoi is a moe-type maid working on a wealthy Osaka estate. In reality, though, she is an undercover detective sent by the police on a special mission to investigate a suspect.
There are all kinds of people living in the back street tenement houses in old Edo. One of them is Ashiya Dosan, the descendant of an Onmyoji who made a name for himself back in the Heian period. Unfortunately, unlike his forefathers, Dosan has not made much of a living off the fortune telling and amulet peddling that he does.