Leia Westoria holds the revered position of saint in the Kingdom of Elshaid, using her magical barriers to protect the realm from monsters. Her life is turned upside down when her younger sister Jill, who has all the attributes of a classic tragic heroine, falsely accuses Leia of abuse. Leia's fiancé, a duke, believes the lies without question, breaks off their engagement, and immediately becomes engaged to Jill instead. Left despondent but determined, Leia throws herself back into her saintly duties. While reinforcing protective barriers in a forest, she is confronted by Crown Prince Eric, a man known for his relentless righteousness, who has also heard the accusations and come to judge her. At her breaking point, Leia does not crumble but instead denies everything and demands he conduct a proper investigation. Taken aback by her forthrightness, the prince apologizes and makes a surprising proposition. Rather than simply clearing her name, he offers her a position as one of his personal bodyguards, inviting her to live in the royal palace where he can keep a close watch on her to determine her true nature.

Once inside the palace, Leia discovers that Prince Eric's life is fraught with danger, facing daily assassination attempts from conspirators within the nobility. Her saintly powers prove to be unexpectedly effective in her new role as a bodyguard, as she often neutralizes threats before they reach the prince. Through these shared ordeals, a bond of trust begins to form between the duty-driven saint and the justice-obsessed prince, whose rigid exterior hides the strain of having few allies. As the story progresses, the narrative reveals that the conspiracy against the prince is tied to corrupt ducal houses, including Duke Berklein, who seeks Eric's death. Leia discovers that her sister Jill is not only complicit with Duke Berklein but is also being used for her rare and untraceable poison magic. From Jill’s own delusional perspective, her actions are justified by a self-centered worldview, making her an unwitting pawn in a larger scheme to destabilize the kingdom.

As the conspiracy escalates, the kingdom becomes embroiled in political turmoil. The King announces plans to revoke special privileges from powerful elite families, prompting further resistance from the nobility. When a deadly poisoning occurs at a popular new establishment, evidence is manipulated to point toward Leia and her allies. Meanwhile, a foreign envoy from the land of Ren arrives with his sister Lingsha, complicating matters with proposals that threaten to separate Leia and Eric. Jill, now imprisoned in a cold cell after her schemes are exposed, is forced to confront her own actions without her usual enablers, leading to a surprising realization about her sister’s mistreatment. With their allies dwindling and the kingdom on the brink, Prince Eric devises a final plan to lure the treacherous duke to a glamorous party where he will confront him directly and expose his crimes for all to see. Ultimately, the series concludes with Leia and Eric preparing to announce their own engagement and secure their happily ever after, having navigated the political conspiracies and family betrayals that sought to tear them apart.