When Crown Prince Cecil is ten years old, he takes Bertia as his fiancée. She claims to have memories of her past life, and says that this is the world of an otome game she once played. She also says that she is a villainess. Cecil is generally bored, but her extraordinary statements spark curiosity in his heart.

Bertia struggles to correct the scenario she has unintentionally altered. At the same time, Cecil enters Halm Academy, a boarding school. During this time in which the two of them spend more and more time apart, Bertia's mother becomes pregnant and it leaves Bertia worried about one thing.

Time passes and Bertia enrolls at Halm Academy, the same school as Cecil. At the same time, Heronia, the heroine of the otome game, also enrolls there. Wishing for a happy ending for Cecil, Bertia fights to bring the two of them together.

In order for Cecil to find happiness with Heronia, avoiding the reverse harem route is essential. For that reason, Bertia has decided to become love's cupid, pairing Cecil's personal aide candidates with other noble ladies.

Heronia grows impatient with the fact that the situation isn't unfolding according to the proper scenario and her attitude toward Bertia worsens. Since the moment Cecil left to study abroad, the harassment that Bertia faces, presumably spurred by Heronia, escalates by the day.

When Cecil learns that Bertia has been pushed down the stairs, he's assailed by an emotion he's never experienced before. Together with the members of the student council, he sets out to take retribution. They gather everyone in the courtyard in order to catch the true culprit.

Upon advancing to the high school division, Bertia begins avoiding Cecil. After turning the situation over in his mind, Cecil visits his father in order to investigate the nature of the Maiden of Destiny. The fated day, the graduation ceremony, quickly approaches.

It's the day of the graduation ceremony. Bertia is resolved to have the tables turned on her and be struck speechless just as the game scenario dictates, but Cecil has prepared something entirely different. Then Heronia speaks up, accusing the villainess Bertia of heinous crimes.

Cecil has been knocked unconscious by the light spirit, Pii-chan, who makes him live in a what-if world in a realm of pure consciousness. The Cecil of that world, where everything unfolds according to the game's original scenario, is as cold and emotionless as a doll, and as Cecil experiences that for himself, his own consciousness begins drifting closer to that of a doll, too.

Cecil wakes after witnessing Pii-chan vanish into nothingness, but Bertia's anxiety hasn't abated even though the judgement event is over. Cecil convinces Bertia to tell him about the different routes the future takes in the game scenario.

At last, Cecil and Bertia commit themselves to each other in the truest sense, but the problem of how to deal with Heronia still remains. In order to keep his promise to Pii-chan, Cecil confronts Heronia.

It's been two years, and the day of Cecil and Bertia's wedding ceremony has arrived. Believing that Bertia deserves to be the happiest bride in the world, Cecil works hard to fulfill her every wish. Watched over by family and friends, their ceremony proceeds in a way that is uniquely their own.