Discussing child homicide is never easy. It’s a subject so heavy it resists clean analysis, forcing us into a moral and psychological fog where certainty collapses. Any attempt to understand it requires navigating an uncomfortable intersection of law, childhood development, trauma, and ethics. While such acts are statistically rare, they demand our attention precisely because they rupture one of our most deeply held assumptions: that childhood is synonymous with innocence. When a child kills, we are left asking questions that have no safe answers—about responsibility, about failure, and about what happens when a conscience is never allowed to form.
In
Gold Rush
, Yu Miri uses the figure of a child perpetrator not to shock, but to probe where responsibility actually lives. The novel is not interested in pathology for its own sake. Instead, it dismantles the idea that there is ever a single cause or a fixed psychological “type.” What emerges instead is a picture of catastrophic convergence: a slow accumulation of environmental pressures that eventually make violence feel not just possible, but inevitable. Yu Miri’s focus is never on excusing the act, but on tracing the pathways that lead to it—and she does so with a clarity that is both unsparing and deeply unsettling.
One useful way to approach Kazuki Yuminaga’s psychological collapse is through what can be called a Developmental Failures model. In a functional environment, empathy, moral reasoning, and selfhood develop gradually through attachment, safety, and consistent care. Children learn limits because those limits are held by adults who are predictable and humane. In Gold Rush, every one of those conditions is systematically denied. Chronic abuse, neglect, and exposure to normalized violence do not merely delay Kazuki’s development—they distort it. Violence becomes not an aberration, but the grammar of everyday life. Harm is no longer clearly “wrong”; it is simply how problems are solved.
Yu Miri’s achievement lies in how meticulously she shows this distortion taking place. Kazuki is not written as a “born monster.” He is written as a child whose inner world is dismantled piece by piece. The novel insists that empathy and conscience are not guaranteed traits, but fragile constructions that require protection. Kazuki’s home is the opposite of such a protective space. His father, Hidetomo Yuminaga, is not simply abusive; he is instructional. From him, Kazuki learns a single, brutal rule: “When words lost their meaning, violence was the only thing you could count on.” This is not a passing observation—it is the foundation of Kazuki’s reality.
Hidetomo’s abuse operates as a pedagogy of power. Violence is relational, transactional, and absolute. The grotesque scene in which Hidetomo negotiates for Hayashi’s daughter, Yoko, reducing her to an obscene exchange value, delivers the clearest lesson of all: human worth is measurable, transferable, and disposable. Kazuki’s response—killing the dog—does not emerge from innate cruelty. It erupts from cognitive rupture. The compassion he still carries for figures like Grandpa Sada, Miho (his older sister), and Kōki (his older brother) crashes violently into the moral void his father enforces. His scream—“You’re disgusting!”—is aimed outward and inward at once: at Hidetomo, at the system he represents, and at the part of Kazuki himself that has been forced to internalize this logic.
What makes this collapse especially tragic is that Kazuki’s capacity for care never disappears. It is punished. His attentiveness toward Grandma Shige, his protectiveness of Miho, his gentleness with Kōki—all of these are treated as liabilities. In the drug-induced hallucination where his friends mock his nurturing instincts, their laughter functions as a social execution. They ridicule the last trace of an uncorrupted self. In Kazuki’s world, compassion is weakness, and weakness marks you as prey. His violent retaliation is not just anger; it is a frantic attempt to defend an identity that is being erased. The paradox is unbearable: the part of him most worth saving is precisely what endangers him.
To survive this contradiction, Kazuki constructs what the novel presents as a layered self. Both Yoko and his mother, Miki, observe this transformation with unease. What they see is not a person, but a performance—“anger superimposed over a smile.” This mask is not deception for its own sake; it is the outcome of developmental failure. Having learned that fear and sadness invite annihilation, Kazuki buries his interior life “in some faraway spot.” Dissociation becomes his refuge. He watches himself from a distance, a spectator to his own emotions. This distance is what later makes violence possible: the act is carried out not by an integrated self, but by a hollowed shell trained to react.
The final trigger—Hidetomo’s threat to send Kazuki to violent confinement—compresses this entire psychological history into a single moment. Within Kazuki’s lived logic, the threat is airtight. His father has always used violence. The coach is known to brutalize children. There is no escape route. When Kazuki thinks, “If I get rid of this person, all my problems will be solved,” the conclusion is horrifying—but it is not irrational. It is the logical extension of everything he has been taught. The calm and “strange willpower” he feels is not madness, but the grim clarity of a trapped animal executing the only survival strategy it knows.
Even the title Gold Rush operates as a psychological metaphor. What is being mined is not just money, but human value—emotional, moral, spiritual. Kazuki is what remains after that extraction: a stripped landscape, emptied of resources. His developmental failures are not accidents. They are the predictable byproducts of a system that consumes people until nothing viable is left.
This brings us to a second framework: the Trauma-Response pathway. Where the first model explains what failed to develop, this one explains what replaced it. Kazuki’s psyche is not merely stunted; it is actively reshaped by trauma into something adaptive and dangerous. His behaviors are not expressions of evil, but learned responses to terror.
Hidetomo’s grooming of Kazuki as his successor is central here. The dog tag, the hidden gold, the promise—“Someday this will be yours”—form a trauma-bonding ritual. Kazuki is invited into the very system that terrorizes him. This is identification with the aggressor in its purest form. To survive, he must stop being prey and become a predator. By adopting his father’s worldview—people as livestock, relationships as transactions—Kazuki gains a sense of control. His contempt for the pachinko customers functions as psychic armor. The “ecstatic smile” he wears is the face of someone who has traded vulnerability for dominance. His attempt to give Kyoko money later confirms the damage: even care has been translated into currency.
This adaptation fractures him further. Dissociation deepens into a full survival mechanism. Miho notices it: “You always seem to be hiding.” During beatings, Kazuki’s mind leaves his body, floating elsewhere, watching from outside the frame. This splitting explains his eerie calm and his sense of unreality. Violence, when it occurs, feels almost automatic—executed by the trauma-self, not the feeling child beneath it.
The attack on Hidetomo is the culmination of this process. It is not ambition or revenge. It is panic. The threat of being handed over to another sanctioned abuser seals every exit. The text captures the shift precisely: fear mutates into a dissociative calm. The “irresistible power” he feels is the illusion of agency trauma provides. In that moment, killing is not hatred—it is escape.
From this lens, Kazuki’s monstrosity is symptomatic. Trauma, left unaddressed, does not merely injure—it reorganizes. The “heir” persona is a coping structure built to contain terror. Dissociation anesthetizes pain but severs empathy. Violence becomes the final malfunction when all other adaptations fail.
The novel’s most crucial pivot arrives with intervention. Yu Miri contrasts two modes of response: Kanamoto’s logic and Kyoko’s compassion. Together, they represent what was missing—and what might still save something.
Kanamoto offers structure. He provides boundaries, consequences, and a vision of adulthood grounded in labor rather than dominance. He sees through the heir persona and challenges Kazuki’s claim that he “became an adult at nine.” The question of “child or adult” is not semantic—it forces Kazuki to confront his fragmentation. Cleaning toilets becomes a radical idea: dignity earned, not extracted.
But logic has limits. When Kazuki begs, “Please be my father,” Kanamoto cannot meet the depth of that need. Structure alone cannot hold terror.
Kyoko can. Where Kanamoto works through language and future-oriented logic, Kyoko intervenes at the level of the body. She becomes a sanctuary before she becomes a guide. Her response to the corpse is the novel’s moral core, and Yu Miri stages it with an almost unbearable intimacy.
Kyoko recoils. She vomits. The text does not sanitize this moment or turn compassion into something graceful. Her body rejects what it sees, just as any human body would. But after that involuntary refusal, she stays. That choice is everything.
She cleans him. She bathes him. This is not symbolic mercy or abstract forgiveness—it is physical, invasive, and profoundly parental. For a child who has learned that his true self is disgusting and punishable, this act rewrites the terms of existence. Kyoko touches what the world has taught him must not be touched. She bears witness not only to the crime, but to the ruined child beneath it, and she does not withdraw her presence.
What matters just as much is that her compassion is not limitless or indulgent. Her ultimatum—turn yourself in, or I leave—is not cruelty. It is boundaried love. Kyoko understands that secrecy is devouring him, that dissociation will continue to hollow him out unless he is forced back into shared reality. She offers him connection, but ties it to responsibility. For the first time in his life, care and consequence arrive together.
When Kazuki finally cries, it is not release. It is collapse. The dissociative shell he has relied on since childhood fractures under the pressure of being seen and held. Fear, grief, and guilt—long sealed away—flood back in. Kyoko’s compassion does not redeem the act, but it makes Kazuki capable of feeling its weight. That capacity, the novel suggests, is the first fragile step toward remaining human.
The final zoo sequence distills everything the novel has been circling toward, shifting from psychological explanation into existential reckoning. The zoo—a place of cages disguised as leisure—becomes the perfect mirror of Kazuki’s inner landscape after the murder.
His earthquake fantasy is not escapism so much as erasure. It imagines an external catastrophe powerful enough to flatten all meaning, to make guilt irrelevant in the face of total destruction. If everything collapses, then nothing has to be answered for. In that imagined chaos, cages break and Kazuki is “pardoned.” An act of God replaces judgment.
But the fantasy immediately curdles. The animals are not liberated; they are seized by panic, bleeding into the city as wounded, dangerous bodies. Freedom without structure becomes madness. Yu Miri makes the implication unmistakable: without containment, Kazuki would not become innocent—he would become feral. The tiger that attacks him is his own violence given form, turning inward. Being shot by the sharpshooters is society’s unavoidable response, the consequence he cannot wish away.
The most devastating moment arrives with the sound of a crying baby. Kazuki’s frantic digging is not about escape, but recovery. He is searching for proof that something untouched still exists inside him—something that would justify survival. What he finds instead is a cricket. The sound that mimicked innocence was never a child at all. Yu Miri refuses sentimentality here. The pre-trauma Kazuki is not buried and waiting to be saved; he is gone. Innocence, once destroyed, cannot be excavated.
When the fantasy collapses and Kazuki realizes “it was the cage,” the metaphor seals shut. The cage is no longer singular. It is physical—the prison he is about to enter. It is psychological—the self permanently reshaped by violence. And it is moral—the inescapable weight of consequence. The sorrow that tears through him, the feeling that his lungs are being ripped out, marks the first moment he fully inhabits reality without dissociation. Awareness returns as pain.
The request to take a new photograph is the novel’s quietest devastation. It is not denial, but mourning. Kyoko and Kōki stand in for the family that never cohered. His attempt to smile is fragile, almost desperate—a performance staged not for others, but for himself. The photograph becomes a relic of a life that almost existed, evidence of what he wanted but was never given.
Gold Rush ends without absolution. What it offers instead is recognition. Kazuki was not driven by greed or ambition, but by deprivation—by the ordinary human hunger for safety, care, and belonging. His crime is the catastrophic misfire of a self that was never allowed to stabilize. Yu Miri’s compassion is unsparing here. She does not excuse him, but she insists we look directly at the cost—not only to victims, but to the child who became capable of such harm. The novel leaves us with its most unbearable question intact: when love and structure arrive too late, what, if anything, can still be saved?
P.S.: For all its psychological precision and moral courage, Gold Rush is not without its fractures. These do not undo the novel’s achievement, but they complicate it in ways that are worth addressing rather than smoothing over.
One recurring issue lies in moments of conceptual incongruence, particularly in how Kazuki’s wealth is framed. Early on, Yoko reflects on the contradiction between Kazuki’s immense financial power and his outward appearance: he looks and dresses like any other ordinary middle schooler. This observation is meant to underscore the strangeness of his position—how wealth does not translate into visible difference or emotional security. Yet elsewhere, the text emphasizes highly conspicuous markers of affluence: the Rolex, the gold tag, the inherited symbols of Hidetomo’s empire. These details pull in the opposite direction, rendering Kazuki simultaneously invisible and ostentatious. The tension is never fully resolved, leaving the reader uncertain whether this contradiction is intentional—meant to signal Kazuki’s fractured identity—or simply uneven characterization. As it stands, the effect is more distracting than productive.
A more substantial weakness emerges in how several secondary characters gradually lose narrative weight and collapse into backdrops. Kazuki’s vagrant friends—Reiji, Takuya, and Kiyoshi—are introduced with clear thematic purpose. In the first half of the novel, they function effectively to show how Kazuki understands relationships as transactional and instrumental, even seeking proximity to people he despises. Through them, Yu Miri sharpens her critique of a social world where connection is stripped of mutual recognition. Yet once this point has been made, these characters vanish almost entirely. They leave no residue. They exert no lasting pressure on Kazuki’s development, no consequences, no memory. Their disappearance makes their earlier presence feel illustrative rather than organic, as if they existed to serve a thesis rather than a lived social reality.
A similar flattening occurs with Kōki, whose narrative potential is far greater—and whose absence is far more troubling. Kōki is one of the people Kazuki loves most deeply. He is also present in the house at the time of Hidetomo’s death and is repeatedly described as having an unusually keen sense of hearing. The novel establishes, almost deliberately, the conditions for recognition. And yet, there is no scene in which Kōki acknowledges what he knows, no moment of confrontation, silence, or even wordless understanding between the brothers. This omission is especially striking given Kōki’s earlier fixation on the “monster” inside Kazuki. The lack of any reckoning between Kazuki and Kōki feels less like restraint and more like a missed moral and emotional encounter—one that could have deepened the novel’s exploration of guilt, love, and recognition.
The most ethically fraught problem, however, lies in the way the novel stages Kazuki’s final movement toward realization at Kyoko’s expense. Before Kazuki confesses his crime to her, he assaults Kyoko in the basement room—an act that forcibly reactivates her own buried trauma from the orphanage, where she was subjected to similar violence by boys. This is not a minor narrative detail; it is a profound violation with its own psychological gravity. And yet, the aftermath centers almost exclusively on Kazuki. Kyoko’s pain, fear, and retraumatization are acknowledged only in passing, if at all. She absorbs the violence, contains it, and then redirects her energy toward caring for Kazuki, prioritizing his collapse, his guilt, his salvation.
In doing so, the novel risks reproducing the very dynamic it otherwise critiques: the expectation that women’s bodies and psyches will serve as sites of endurance and repair for male damage. Kyoko’s compassion is undeniably powerful, but it is also costly—and the cost is largely unspoken. There is no sustained space in which Kazuki is made to confront what his assault does to her, no moment where her suffering interrupts or complicates his arc. Her trauma becomes another silent resource expended so that his humanity can be restored.
This does not invalidate Yu Miri’s vision, but it does leave a bruise on the text. Gold Rush is relentless in tracing how violence reproduces itself across generations, yet in this final exchange, it hesitates to fully reckon with how that reproduction can occur even within acts of care. Kyoko survives, but her survival is folded into Kazuki’s story rather than allowed to stand as its own moral demand. The result is a deeply unsettling imbalance—one that lingers long after the novel ends, and one that readers are right to question rather than accept as collateral damage.