The story centers on third-year high school student Jiro Yakuin, who gets saddled with his gyaru classmate Akari Watanabe for the class's "marriage training" project about practicing to be a married couple. Jiro is the complete opposite of Akari, but the two know that if they do well they will be able to switch partners to end up with their respective crushes, and so they force themselves to act like the perfect married couple.
Kaori is a single mother and she raises her high-school age daughter Futaba. Her daughter is in a rebellious phase and ignores her mother. Kaori decides to take measures to communicate with her daughter and also get some revenge. Kaori creates messages in her daughter's bento meals.
In this adaptation of the popular eponymous mystery novel by Keisuke Matsuoka, Paris provides the gorgeous backdrop for a grand intrigue involving the world’s most iconic artistic treasure: the Mona Lisa. Minds will be blown, puzzles will be solved, but will a 500-year-old curse be removed?
