Plot
Haruse Chiaki, the owner of a struggling used bookstore named "Kotatsu-do," was facing the impending closure of his shop amid despair.
Before him appeared a mysterious beautiful girl, Shinohara Ren.
Ren offered to help rebuild the bookstore, but in exchange, she demanded that Chiaki "marry" her.
Pushed by Ren, who said she needed to understand the bonds of family, Chiaki reluctantly accepted a contract marriage despite his confusion.
And so began an unusual newlywed life with Ren, who aimed for a "perfect family."
Though bewildered by Ren, who often defied common sense, Chiaki gradually found himself drawn to her.