[Deceive Dielo Argenta and steal his chastity.] This was the vile order from Duke Alloge, the contemptible father who branded his daughter’s back with the enemy’s name. The protagonist finds herself reincarnated as Krua Alloge, a villainous extra in the 19+ angsty novel "The Three Ducal Houses." Disguised as Phero, the fake fated partner of Duke Argenta, she is tasked with infiltrating the Argenta family and bringing it to ruin. But rather than follow the original plot, she chooses to share a bed with the enemy to avoid her doomed fate. "Let’s get married—just for one year." They enter into a contract marriage for mutual benefit, pretending to be a passionate newlywed couple while secretly working to protect Argenta from within. But one year later, as Krua prepares to leave Argenta behind, Dielo reveals his true nature—one he had kept hidden until now?! "I thought you were wise... But how can you know one thing and be blind to the other?" Can Krua escape Dielo’s gentle yet obsessive love?