Countess Lilygen, mourning the death of her mother, suddenly recalls memories of her past life. She realizes she has been reincarnated into the world of her favorite novel. However, she’s not the villainess, but rather the mob-character half-sister of the villainess! As the plot of the novel rushes through her mind, she recalls her tragic fate—being mistreated by her family, her once-esteemed count family on the verge of ruin, and her sickly father burdening her with responsibility. Lilygen’s response? Absolutely not. Rather than facing a grim future, she decides to abandon her family and save the frontier territory from a demon outbreak with the help of Theobald, seeking refuge with her uncle, the Margrave Ashguile. What adventures await her as she takes fate into her own hands?