A tomboyish office worker dies in an accident and awakens in the world of an otome game she had been playing, reincarnated as the villainess Serena. In every route, Serena is destined for ruin—exile, imprisonment, or even death—for interfering with the heroine's love life. Refusing to accept such a fate, she decides to live freely and use her newfound cheat-level athleticism to stand out.

Her bold actions catch the attention of her fiancé, Roberto, a cold and distant noble who suddenly becomes fiercely obsessed with her. Though she has always disliked the perfect, domineering love interests typical of otome games, Serena's body cannot resist the pleasure he brings her.

As Roberto's possessiveness deepens, she finds herself trapped in a passionate, doting route within the all-boarding academy. The line between ruin and desire blurs as their intense pre-marital negotiations begin.