After a traumatic encounter with her stalker in Korea, a young woman reincarnates into another world as Lydia, the eldest daughter of the esteemed Widgreen family. Life as a noble in a fantasy novel is one of indulgence and comfort until Lydia discovers a sacredly kept secret—she is adopted. Worse yet, she is destined to die at the hands of her psychopathic younger brother, Ash, who will fall in love with the story's gentle heroine, Agrita Grace.

Lydia knows Ash's extreme personality too well; just as he loses all common sense and resorts to violence to ensure her happiness, he will pass that same fixation onto Agrita. Once he learns that he shares no blood ties with Lydia, his loving gaze will turn sadistic, and he will not hesitate to behead her. Desperate to live, Lydia concocts a plan to escape Ash's murderous clutches on the day he and Agrita meet. However, a new problem arises: the world seems to want Agrita dead, and Ash shows nothing but indifference to her fate.