A Japanese office worker named Watase Rin dies and reincarnates as Rosalia, the villainess of an otome game whose story is packed with death flags. Determined not to repeat the character's tragic fate, Rin resolves to live happily and peacefully in this new life. She uses her complete knowledge of the game's plot to systematically dismantle each death flag before it can trigger. However, her attempts to lie low and be a normal duke's daughter backfire spectacularly. She accidentally contracts with powerful spirits, applies modern-world knowledge to assist her father, the prime minister, in his political work, and even goes for casual strolls with a sacred beast. Before she knows it, she ends up triggering events meant for the game's heroine instead of the villainess. The story follows Rin's chaotic, self-unaware rampage through the original story's events as she desperately tries to avoid her doomed fate all while pursuing a romance with Dirk, a beastkin knight she adored in her past life and her favorite character from the game. The narrative balances comedy and fantasy action with Rin's accidental accumulation of power and influence, and explores how her genuine kindness and determination reshape the world around her.