The story begins with Sugaya Sousuke and Izaki Shion, childhood friends and classmates, finishing their duties as class representatives. Shion, who appears younger than her age, expresses her desire to go home, while Sousuke reminds her about her declining grades, a concern her mother had also voiced. Shion reacts defensively, telling Sousuke not to interfere, but he reveals he's been asked by her mother to keep an eye on her. Their playful bickering is interrupted by Izumi Kaname, the student council president, a stern and impeccably dressed student. Shion, in a moment of mischief, falsely accuses Sousuke of sexual harassment. Kaname, taking the accusation seriously, physically restrains Sousuke and threatens to involve a teacher.
Sousuke finds himself in the student guidance office, facing his homeroom teacher, Yamase. Yamase, aware of Shion's retraction of the accusation, assures Sousuke that the matter won't escalate to the principal, but warns Shion. Sousuke, though relieved to avoid expulsion, feels a sense of weariness and frustration, deciding to go home early.
The next morning, Sousuke resolves to stop interfering in Shion's life, acknowledging his overreach. He notices Shion's absence from their usual morning commute. Shion arrives just before homeroom, and Sousuke, though aware of her gaze, ignores her. After school, Shion apologizes for her actions, which Sousuke accepts, also apologizing for his harsh words. However, as he tries to leave, Kaname intercepts him, demanding he come to the student council room. There, Kaname criticizes Sousuke for his behavior towards Shion, implying he caused the situation. Sousuke, angered by her lack of apology for her physical actions and her interference, argues that it's a personal matter between him and Shion.
That evening, Shion visits Sousuke's home to apologize again. Sousuke, still upset by Kaname's behavior, is short with Shion, telling her he won't interfere anymore and that she should do as she pleases. Shion leaves in tears, and Sousuke regrets his harshness.
The following day, Sousuke is confronted by Tsubaki Mizuka, a friend of Shion's, who explains Shion's distress. Mizuka acknowledges Shion's fault and asks Sousuke to maintain their friendship. Sousuke explains his decision to distance himself, but Mizuka senses his underlying anger towards Kaname. He recounts his encounter with Kaname, and Mizuka is shocked by the student council president's behavior. Mizuka persuades Sousuke to reconcile with Shion, and they agree to return to their previous dynamic, though Sousuke states he won't be as overbearing.
Later, during lunch, Kaname summons Sousuke to the student council room again, accusing him of not reflecting on his actions. Sousuke argues that Kaname is the instigator and that she should focus on her duties. Kaname demands he apologize to Shion by prostrating himself, while Sousuke insists she apologize for her physical assault. Shion intervenes, defending Sousuke and stating she was joking. Kaname, unfazed, insists Sousuke come to the student council room after school.
After school, Sousuke heads to the student council room, accompanied by Shion. Kaname announces a new school rule: boys must maintain a one-meter distance from girls, effectively targeting Sousuke and Shion. Sousuke accuses Kaname of using her position for personal vendettas. Kaname claims to want a comfortable school environment, but Sousuke challenges her, suggesting she should transfer to an all-girls school if she dislikes co-ed interactions. When Kaname falters, Sousuke presses her, and Shion defends Sousuke, stating he did nothing wrong and that Kaname's actions are bullying. Other student council members express their disapproval of Kaname's excessive rules and confrontational approach. Sousuke leaves, telling Kaname to focus on her actual duties.
Sousuke begins working part-time at a cafe as a kitchen assistant. He experiences escalating harassment from his superiors, the head chef and manager, who seem to target him without clear reason. This includes being forced to work longer hours and being unfairly reprimanded. His friends, Shion and Mizuka, visit him at the cafe, witnessing the chef's rude behavior towards Sousuke. Mizuka intervenes, highlighting the chef's unprofessionalism towards customers. Sousuke, emboldened by his friends' support and the chef's insults towards them, retaliates, leading to his dismissal.
The harassment escalates at school. Sousuke finds thumbtacks in his shoes and abusive messages. He suspects a female student named Hashima Wakaba, a member of the disciplinary committee, and her friends. After finding his shoes vandalized with scissors and spoiled milk, Sousuke retaliates by pouring water and milk into Hashima's shoes, leaving a threatening note.
The next day, Sousuke is challenged to a duel by Asahiga Yuto, the student council president's equal in fame and the disciplinary committee chairman. Asahiga wants Sousuke to join the disciplinary committee to help him oppose the student council president. Sousuke, despite his reluctance and the fact that he was targeted by Hashima, agrees to a game of Memory to decide. Asahiga wins, forcing Sousuke to join the committee.
Sousuke continues to be harassed, finding more thumbtacks and abusive messages. He realizes the harassment is escalating and that he needs to identify the culprit. He confronts Hashima and her friends, who are amused by his predicament.
The narrative then shifts to a more serious incident. Sousuke intervenes when he witnesses a mother, who is clearly overwhelmed and distressed, physically abusing her young daughter, Aimi. The mother reveals she was abandoned by Aimi's father, her former boss, and is struggling with single parenthood. Sousuke confronts the mother, criticizing her actions and her blaming of the child. The situation escalates, and Sousuke is physically assaulted by the mother's male companion, who is revealed to be Aimi's father. Sousuke, despite being injured, provokes the man, leading to his arrest by the arriving police. Sousuke, with Shion's help, ensures Aimi is safe and taken to her home.
Later, Sousuke and Shion visit Aimi's apartment, which is in a state of squalor. They find Aimi's father, who is abusive towards her. Sousuke intervenes, and the father assaults him. Sousuke, with the help of Shion and the police, manages to get the father arrested. Sousuke's actions, though risky, ultimately lead to Aimi's rescue from an abusive environment.
The story concludes with Sousuke receiving a challenge from Asahiga for a duel, seemingly related to his new role in the disciplinary committee. Sousuke also finds his shoes vandalized again, indicating the harassment is ongoing.
