A dating sim enthusiast is crushed to death by her collection of otome games and wakes up in the body of Reine Waynewright, the heroine of her favorite fantasy romance game. She quickly realizes she has arrived at a critical moment just after the original Reine attempted suicide due to relentless bullying at Heartfelt Academy, a prestigious magical school where students are ranked from S to F. As an F-rank student with no magical talent, Reine is snubbed by her potential love interests and tormented by her classmates, putting her on a clear path toward a Bad Ending where she is likely to be expelled or worse.

Pleading amnesia to explain her sudden personality change, the new Reine resolves to fight her fate. Rather than relying on knowledge of the game's plot, which she never finished, she decides to study diligently, practice her magic, and work her way up the school's rigid ranking system to improve her standing and secure a happy future where she can fall in love. Her cheerful determination gradually begins to change her relationships, starting with her mysterious older step-brother Julius, a high-ranking student who has always kept his distance but now becomes her protector and tutor. She also befriends a quiet, grumpy classmate she nicknames Yoshida, who helps her with her studies, as well as Reinhardt, another F-rank student she saves from bullying who reveals himself to be a potential romance route.

The story takes place primarily at Heartfelt Academy, a fantasy institution where social status is determined by magical ability and academic rank. Reine also returns to the Waynewright family estate, where she must navigate a dysfunctional noble family, including a jealous step-sister who harbors a disturbing obsession with marrying Julius and views Reine as a romantic rival despite their sibling relationship.

Several notable narrative arcs develop across the series. The initial arc focuses on Reine's intense studying and preparation for the rank exams, where she gradually proves her worth to her skeptical classmates and catches the attention of several handsome love interests, including the previously indifferent prince. A second arc involves a summer retreat to the Waynewright estate, where Reine encounters her dreaded cousin Cecil, who agrees to tutor her in exchange for information about his mysterious academy classmate, a girl who calls herself a heroine, leading Reine to suspect another person has been reincarnated into the same game world. A later arc sees Julius's jealous and possessive behavior intensify when Reine visits Yoshida's family home, where she must face a challenge from Yoshida's older sister to prove the sincerity of her feelings. Throughout these events, a central mystery persists regarding Julius's true relationship to Reine, his hidden motives involving revenge, and the secret he refuses to reveal about why he is not actually her blood relative.