Kotono Miyatsuji, a student at Ikaruga High School, navigates the complexities of adolescence alongside her sister Suzuyo under the watchful influence of their mother, Kasumi, the head of the school’s trustee board. Both sisters find themselves drawn to Kaneshiro Shoichi, a peer whose singular focus rests on Morisawa Maiko, the school physician. When Kaneshiro risks expulsion due to academic failure, he conspires with Maiko to steal an examination disk from the principal’s office—a desperate act that entangles Kotono through her unspoken affection for him. Her participation intertwines with tensions of loyalty, yearning, and the shifting power dynamics within the school. The theft and its repercussions mark a pivotal turn in Kotono’s story, shaping her choices and relationships amid the collision of personal emotion and institutional consequence.