An office worker and dating sim enthusiast dies in an accident and awakens as Reine Waynewright, the adorable heroine of her favorite fantasy otome game. She quickly realizes her situation is dire. At Heartfelt Academy, a prestigious magical school, Reine is an F-rank student, the lowest possible class. She is routinely bullied by her classmates, possesses almost no magical talent, and is completely ignored by all the game's romanceable love interests. Having never finished the game in her previous life, she cannot recall the exact details of the story, but she knows one thing for certain: her current path leads directly to a Bad Ending.

Refusing to accept this fate, Reine uses her adult tenacity and knowledge of the game's mechanics to fight back. She resolves to study relentlessly, practice her magic, and pass her exams to raise her rank. Her goal is not just survival but to change her destiny completely by making genuine friends, improving herself, and perhaps even finding love. Her initial allies include her enigmatic stepbrother, Julius, whose protective and sometimes possessive behavior toward her confuses Reine, who still believes they are simply siblings. She also befriends fellow underachievers like Reinhardt, revealing new potential romance routes she never knew existed.

As Reine works her way up from F-rank, the story unfolds through several key narrative arcs. An early arc focuses on her rigorous studies and the revelation of a mysterious labyrinth during a school trip, where she must protect her friends from a powerful final boss. A later summer retreat to the Waynewright estate introduces her dreaded cousin Cecil and hints at the presence of another person who may have also been reincarnated into the game world. Subsequent volumes see her navigating Julius's increasing jealousy and facing challenges from the families of other love interests, all while trying to unravel the secrets of her own in-game past and the true nature of her relationship with her brother. The series is set within the rigid social hierarchy of Heartfelt Academy, where a student's rank dictates their treatment and opportunities, and at the Waynewright family estate, where political tensions simmer beneath the surface. An anime adaptation has been announced and is in production.