Cecil Glo Alphasta, crown prince of the kingdom of Alfasta, is a prodigy in every field. From a young age, he masters magic, swordsmanship, and academics with such ease that life holds no challenge or surprise. He is numb to emotion and profoundly bored. That changes when he is betrothed to Bertia Ibil Noches, the daughter of the prime minister. On their first meeting, Bertia announces with conviction, “I am a villainess!” She claims to possess memories of a past life and insists that the world she now inhabits is the setting of an otome game. In that game, she is destined to persecute the heroine, be denounced by Cecil, and meet a ruinous end. Determined to follow that script, she declares that her mission is to drive a wedge between Cecil and the “destined maiden” so that he can be happy with his true love.

Cecil, initially amused by what he assumes is a delusion, decides to play along and observe her. Bertia throws herself into schemes to act the part of a wicked noble — plotting to ruin the heroine, trying to make Cecil despise her, and orchestrating events that she believes will lead to her own downfall. But her efforts are always clumsy and misdirected. Her version of “evil deeds” comes across as earnest kindness, and instead of pushing people away, she unintentionally wins their affection. When a plague that she foretold actually breaks out, Cecil realizes her predictions are genuine and takes her claims more seriously.

As the story unfolds, Cecil’s detached fascination grows into genuine interest, then deep affection. He finds Bertia’s relentless, naive dedication endearing and begins to subtly manipulate events to keep her close. Bertia, meanwhile, remains oblivious to his feelings, convinced that her role is to be rejected and banished. The manga follows their relationship through childhood, enrollment in a royal academy, the appearance of the apparent heroine Heronia Inderon, and the mounting pressure of the game’s narrative. Obstacles include schoolyard rivalries, meddling from light spirits, and Heronia’s own ambitions. Bertia’s attempts to push Cecil toward Heronia only strengthen his resolve to be with Bertia.

The story builds toward the graduation ball, where the game’s climax would normally see Bertia publicly condemned. Instead, Cecil proposes marriage. A confrontation with Heronia triggers the power of a light spirit, trapping Cecil in an illusion that shows the game’s original unhappy ending. He breaks free, fully aware that Bertia’s true nature is nothing like the villainess she pretends to be. The final volumes depict their wedding and married life, with Cecil ensuring Bertia’s happiness and the couple eventually welcoming children. The narrative is told entirely from Cecil’s perspective, focusing on his growing captivation with his bizarre, good-hearted fiancée. The manga adaptation, illustrated by Natsume Hasumi, spans six volumes and covers the complete story from first meeting to happily ever after.