Yeojuingongui Cheotsarangeul Taraksikyeo Beorimyeon

A character named Karina Apocalita is a member of a race considered evil in her world. She becomes possessed by a body that entered a book. The original story features Paladin Ren, who is the first love of the novel's protagonist and nearly saves its main character. As events unfold, Ren begins to doubt his faith and loses his white blonde hair, leading to his corruption. He eventually comes to understand and share Karina's plight. Karina expresses a mutual desire with Ren, and their connection deepens. Ren is unable to sever their bond, expressing regret for his actions.