Tatiana, a half-demon/half-human, was orphaned as a child by a horrific war between the demon and human kingdoms. A human Duke took her in, but only so that he could take advantage of her special skill: Tatiana can speak Shadowtongue, the native language of demons, unspeakable by anyone devoid of demon blood. Despite the abuse she receives from the Duke's family, she works hard as an interpreter between the kingdoms, in hopes of maintaining peace and winning her family's affection.
Her efforts prove worthless, however, when she is unwittingly used by the Duke as a political pawn and killed for her actions. Just as Tatiana thinks she has breathed her last—she wakes up, one year prior to her death! Determined not to beg for love any longer, and armed with advanced knowledge of the villainous deals made by the Duke, Tatiana flees to the Demon High Court and offers her knowledge to the Demon King Luther himself in exchange for sanctuary. The notoriously cold-hearted warrior king is intrigued by the bold half-demon woman's offer and accepts her proposal, not expecting that she will also work her way into his heart.