In the 15th year of the Genroku era in the Edo period, a couple, Oiran, Oran, and Shinzaburo, a young man who runs a money changer, vowed to each other that they would definitely become husband and wife in the next reincarnation. ――Since then, 300 years have passed. Ran Harukawa, an 18-year-old beautiful girl who is the reincarnation of Oran and has memories of her previous life, rushes to Shintaro, the reincarnation of Shinzaburo. However, this Shintaro, who came to visit Ran, who is a sloppy and ridiculous man, takes her virginity, thinking that she is a dispatch type prostitute. Shintaro, who has no memory of her previous life, is puzzled, but she is overpowered by Ran and begins a strange cohabitation. Can Shintaro regain her memories of her previous life and make Ran happy? A slightly naughty heartful romantic comedy!