Eita Kidou is an academic-focused high school freshman who harbors a deep, pragmatic disdain for romance. Convinced that love brings only emotional ruin and distraction, his singular ambition is to graduate top of his class and secure a full scholarship to medical school. His peaceful, studious life is abruptly shattered by Masuzu Natsukawa, the school's most popular and breathtaking beauty. Blackmailing Eita with a compromising childhood diary that exposes his cringe-inducing chuunibyou past, Masuzu forces him into a fake relationship. Her true motivation is to deflect the relentless, unwanted romantic confessions of her peers by appearing "taken." Desperate to protect his humiliating secrets, Eita reluctantly complies.However, Masuzu's elaborate ruse quickly backfires. The announcement of their fake coupling provokes the jealousy and fury of Eita's childhood friend, Chiwa Harusaki, who has secretly loved him for years and fights fiercely to reclaim his affection. Soon, the chaotic triangle expands into a multi-sided romantic battlefield. They are joined by Ai Kisaki, Eita’s fiercely protective middle school friend who operates under a strict code of tsundere denial, and Himeka Akishino, an eccentric chuunibyou girl who instantly recognizes Eita's dark fantasy alter-ego and demands he become her "knight."Caught in a whirlwind of
emotional turmoil, Eita finds himself besieged by these brilliant yet socially awkward girls, each staking a claim on his heart. Despite his initial resistance to romance, the facade begins to crumble as he is forced to confront the genuine vulnerabilities and painful pasts of his suitors. Chiwa is haunted by a debilitating sports injury that robbed her of her gymnastics dreams; Ai battles the immense pressure of living up to her family's expectations; and Masuzu navigates a profoundly lonely home life dictated by a wealthy,
emotionally distant family.As the boundaries between acting and reality increasingly blur, Eita is compelled to abandon his emotionally detached cynicism. He steps up to genuinely support each girl, helping them confront their inner demons and reconcile with their pasts. Through these intense trials, Eita learns that love is not merely a foolish distraction, but a powerful, transformative force. Ultimately, while the chaotic harem dynamics and comedic rivalries persist, the series culminates in a heartwarming resolution where Eita fosters deep, authentic emotional connections, finally discovering that opening his heart to others is the greatest cure for his own loneliness.