Opening
On the last day of school, middle-school teacher Yūko Moriguchi turns homeroom into a confession that detonates her students’ sense of safety and truth. What begins as a calm talk about health and “Milk Time” spirals into murder, culpability, and an act of icy Revenge that reshapes the lives of everyone in the room. A new school year then exposes the fallout: secrets, manipulation, and violence echo through the class as power shifts and guilt hardens into action.
What Happens
Chapter 1: The Saint
Moriguchi delivers a single, composed monologue to her unruly class. She announces her resignation, then unspools a personal history centered on her four-year-old daughter, Manami Moriguchi, and Manami’s father, the famed “Saint” teacher, Masayoshi Sakuranomi. Because he is HIV-positive, they never marry and choose to raise Manami separately to shield her from prejudice—a story Moriguchi uses to make her students squirm and to frame her fiercest identity: mother as protector. The theme of Motherhood and Family Dysfunction sharpens as she contrasts her love with the coddling negligence she sees in her students’ families.
She recounts the official version of Manami’s death—an accidental drowning at the school pool—then overturns it. Manami, she says, is murdered by two students in the very room. Refusing to go to the police, she cites the failures of the Juvenile Law, which would shield the underage killers from meaningful punishment. She names them only as Student A and Student B: Student A, later revealed as Shūya Watanabe, is a narcissistic prodigy desperate for recognition; Student B, Naoki Shitamura, is a malleable follower. Shūya builds an electrified anti-theft purse and, jealous of a sensationalized youth criminal, tests it on Manami to make headlines.
The climax strips away the class’s illusions, exposing the gap between appearances and truth—Perception vs. Reality. Shūya’s device only stuns Manami. Naoki, panicking, throws her unconscious body into the pool, and she drowns. Moriguchi then unveils her plan: since the law fails, she has spiked the milk cartons of the two boys with her late fiancé’s HIV-infected blood. “You’ll have years,” she tells the class, to consider the value of life before the disease may appear. She dismisses them in silence, leaving terror—and two killers—to curdle in their seats.
Chapter 2: The Martyr
A new year begins with a new voice: Mizuki Kitahara, the class president, writes a long letter to Moriguchi describing a classroom humming with tension and denial. A relentlessly cheerful rookie teacher nicknamed “Werther” takes over, unaware of the darkness beneath the surface. Naoki vanishes from school, sunk in a breakdown; Shūya shows up daily and is immediately frozen out. One afternoon, a popular boy, Yūsuke, lobs his milk carton at Shūya’s back—an act that opens the floodgates.
An anonymous text transforms cruelty into a game. A point system rewards tormenting Shūya, while any student who refuses risks being branded a “Friend of the Killer.” Cornered by Ayako’s clique, Mizuki is forced to throw a milk carton at a bound and gagged Shūya. For a split second she feels euphoric release—followed by crushing shame and Guilt and Atonement. The bullies make her “kiss” Shūya for a blackmail photo. That night, Shūya messages her with a lab result: he is HIV-negative. Mizuki confesses she suspected Moriguchi’s story was a bluff; she tested cartons the day of the confession and found no blood. Moriguchi’s revenge, they realize, is psychological.
Isolated and newly allied, Mizuki and Shūya become lovers. Armed with his clean test, Shūya turns fear into a weapon: he smears his own blood on bullies, letting their terror of infection do the work. Meanwhile, Werther fixates on “saving” Naoki and stages a mortifying public appeal outside the boy’s home, humiliating Naoki and Naoki’s Mother. That night, pushed past his breaking point, Naoki kills his mother. Mizuki admits she has long loved Naoki and now loathes Werther for triggering the tragedy. She ends her letter with a challenge to Moriguchi: “What do you think of your revenge now?”
Character Development
Shifting narrators recast motives and identities in harsher light. Each character’s need—for love, recognition, or absolution—drives choices that escalate harm.
- Yūko Moriguchi: From grieving mother to calculating architect of fear. She presents logic and restraint while practicing moral transgression outside the law.
- Shūya Watanabe: Starts as a brilliance-obsessed narcissist; bullied into silence, he then exploits the class’s panic to regain power through intimidation.
- Naoki Shitamura: A pliable accomplice overwhelmed by dread; isolation and terror metastasize into psychosis and matricide.
- Mizuki Kitahara: A conscientious leader bent by peer violence; guilt draws her toward Shūya, even as her buried love for Naoki fuels rage and ambiguity.
- Werther: Naive idealist who mistakes cheer for compassion; his public “help” worsens stigma and catastrophe.
- Naoki’s Mother: Strained caregiver under social pressure; her humiliation and fear culminate in tragedy at her son’s hands.
Themes & Symbols
Revenge drives the plot but operates as psychological theater rather than corporeal punishment. Moriguchi’s bluff corrodes the class from within: fear substitutes for law, and rumor outpaces reality. Her act spawns copycat cycles—students exacting “justice” on Shūya, Shūya terrorizing them in return, Mizuki contemplating her own retaliation—showing how vengeance multiplies rather than resolves harm.
Justice and the law stand exposed as inadequate for juvenile crime, prompting extralegal answers that prove equally, if not more, destructive. The novel’s method—confessions that contradict prior accounts—embodies perception versus reality: an “accident” masks murder; “infection” masks a bluff; “guidance” masks public shaming. Adults misread crises; children weaponize misunderstanding.
Symbol: milk. It begins as nourishment and health, then curdles into a conduit of disease and punishment. Moriguchi turns milk into a threat; the class turns it into ammunition; Shūya’s blood play makes it a stage prop for terror. The white carton becomes a ritual object of control.
Key Quotes
“Student A and Student B killed Manami.”
- Moriguchi’s clinical phrasing strips comfort from the room and de-individualizes the killers, asserting power while shielding identities. It also indicts the entire class by forcing them to wonder whom they have sat beside.
“I injected HIV-infected blood into their milk.”
- The sentence rebrands innocence as danger. Whether true or not, it weaponizes belief, proving that fear can punish as effectively as force.
“Friend of the Killer.”
- The label industrializes cruelty. By threatening social death, the bullies conscript bystanders and convert harassment into a game with rules and rewards.
“I’m HIV-negative.”
- Shūya’s revelation flips the power dynamic. The truth frees him privately, but he chooses to keep the lie alive publicly, showing how knowledge can become a tool of domination.
“What do you think of your revenge now?”
- Mizuki reframes the moral ledger. The question implicates Moriguchi in the chain reaction that leads to humiliation, violence, and a mother’s death.
Why This Matters and Section Significance
These opening chapters build the novel’s core engine: confessional voices that fracture truth and show how one act reverberates through a community. Chapter 1 operates as a taut, closed-room thriller that seeds every major motif—failed institutions, parental love, and the seductive logic of punishment. Chapter 2 widens the lens, proving that the aftermath often eclipses the original crime: a bluff, not a virus, births a bullying economy, a predatory romance, and a murder.
Together, they establish a Rashomon-like structure in which each narrator revises the last, forcing readers to question causality and blame. Adult misreadings and youthful extremity feed each other, turning a classroom into a laboratory for fear—where milk, tests, and texts decide who suffers next.