Shall we spend our lives together?” Grace is a noblewoman who operates in the shadows for the sake of her country—a villainess in public and a spy in private. She is tasked with a one-year to Felix, the young head of an enemy ducal house, with the promise of her first-ever [vacation reward] upon completion! While serving as Felix’s bodyguard during their engagement, Grace thinks, “Since our families hate each other, it’ll be easier to focus on the mission if he just keeps loathing me!” But for some reason, he ends up becoming abnormally obsessed with her instead…!?