Food is never just food. In Butter by Asako Yuzuki, it's a weapon, a seduction, and a very greasy mirror held up to the face of modern Japan. If you haven't heard of this novel yet, it’s basically a cultural phenomenon that started in Japan and has been steadily melting its way through the international bestseller lists since its English translation. It is loosely based on a true story. A real-life "con-woman killer" named Kanae Kijima. She didn’t look like a femme fatale. She wasn’t thin. She wasn't young. But she could cook, and men died after eating her meals.
Yuzuki takes this premise and turns it into something much more complex than a standard true-crime thriller. It’s a book about hunger. Not just the "I forgot to eat lunch" kind of hunger, but the deep, gnawing social starvation for validation that women feel in a society that demands they be thin, hardworking, maternal, and invisible all at once.
The Plot: More Than Just a Recipe
The story follows Rika, a journalist who is—honestly—struggling. She’s overworked. She eats convenience store ramen at her desk. She’s tired. She decides to write about Manako Kajii, the woman in prison for allegedly murdering several men while taking their money. The catch? Kajii won't talk to anyone who doesn't appreciate food.
To get the interview, Rika has to eat. Specifically, she has to eat the things Kajii loves. This starts a bizarre, sensory-heavy relationship where the prisoner begins to remote-control the journalist's life through culinary instructions.
Kajii is obsessed with butter. She hates margarine. She views the "white fat" as a symbol of indulgence that most people are too scared to touch. "There are two things I cannot tolerate: feminists and margarine," Kajii famously (and controversially) says in the book. It’s a line that makes you want to throw the book across the room while simultaneously wanting to know what she says next.
Why This Book Hits Different
Most books about serial killers focus on the "how" or the "why" of the murder. Butter by Asako Yuzuki focuses on the "how" of the eating. The descriptions of soy-sauce-drizzled butter on hot rice are so visceral they’ve sparked a literal surge in people trying the recipe at home. It’s food porn with a side of existential dread.
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You’ve got to appreciate how Yuzuki handles the pacing. Sometimes the prose is dense and rich, like a heavy sauce. Other times, it’s short. Sharp. Like a knife.
The book dismantles the "shame" associated with female appetite. In Japan, and frankly everywhere, women are often taught to take up as little space as possible. Kajii rejects this. She is unrepentantly large. She is unrepentantly hungry. She doesn’t apologize for the space she occupies or the butter she consumes. Rika, the "normal" one, finds herself becoming more "alive" as she gains weight and begins to prioritize her own pleasure over her career's demands. It’s a subversion of the typical makeover trope. Usually, the protagonist gets thin to find happiness. Here? She gets fat to find herself.
The Real-Life Inspiration: Kanae Kijima
You can't talk about Butter by Asako Yuzuki without talking about the "Konkatsu Killer." In 2009, Kanae Kijima was arrested for the deaths of three men, though she was suspected in more. She met them on dating sites. She was a talented cook. The Japanese media was obsessed with her because she didn't fit the mold of a "black widow." She wasn't "traditionally" beautiful.
The public's fascination—and vitriol—was rooted in a weird kind of anger: How could a woman who looks like that trick these men?
Yuzuki uses this real-world bias to fuel the novel. Kajii, the fictionalized version, uses her domestic skills as a form of power. She knows that a man coming home to a perfectly cooked, butter-laden meal is a man who is vulnerable. It’s a dark take on the "way to a man's heart is through his stomach" adage.
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Social Commentary Wrapped in Fat
The book is a scathing look at the "salaryman" culture and the intense pressure on Japanese women to be "女子力" (joshi-ryoku) or "womanly." This means being good at cooking, being cute, and being supportive. Kajii weaponizes these expectations. She performs the "perfect woman" role so well that she can literally get away with murder (maybe).
- The misogyny is internal and external.
- The friendship between Rika and her best friend Reiko provides the emotional backbone.
- The office politics are depressing and accurately soul-crushing.
It’s a long book. Over 400 pages. But it needs that length to let the characters marinate. If it were a fast-paced thriller, you’d miss the subtle shift in Rika’s psyche. You need to feel the weight gain with her. You need to smell the truffles.
Dealing With the "Slow Burn"
Some readers find the middle section a bit sluggish. Honestly, that’s sort of the point. It mirrors the lethargy that comes with over-indulgence. It’s a sensory overload. If you’re looking for a "Girl on the Train" style page-turner where a body drops every three chapters, this isn't it. This is a character study. It’s about the slow erosion of a woman’s defenses.
The ending doesn't tie everything up in a neat little bow. It’s messy. It’s greasy. It leaves a film on your skin, much like butter does.
Practical Insights for Readers
If you're planning to pick up Butter by Asako Yuzuki, go in with an open mind and an empty stomach. But also, be prepared for some discomfort. The book tackles fat-shaming in a very blunt way. Some of the dialogue from the male characters is intentionally revolting.
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- Don't read it while on a diet. You will fail. The descriptions of Echiré butter and gourmet French cooking are designed to break your willpower.
- Look up the geography. The book moves through specific parts of Tokyo and suburban Japan. Understanding the setting helps visualize the isolation Rika feels.
- Research the Konkatsu Killer. Knowing the basics of the Kanae Kijima case adds a layer of "truth is stranger than fiction" to the experience.
- Pay attention to the side characters. The men in the book are often one-dimensional, but that’s a deliberate choice. They are the consumers. The women are the producers.
Butter by Asako Yuzuki is ultimately a book about reclamation. Reclaiming your appetite, your body, and your right to be "unpalatable" to society. It asks a terrifying question: Is it better to be a "good" woman who is miserable and hungry, or a "bad" woman who is satisfied and full?
Next Steps for the Curious
If the themes of this book resonated with you, there are a few ways to deepen the experience. First, try making the "Kajii Rice" (hot rice, a thick slab of butter, and high-quality soy sauce). It’s a simple dish that carries the weight of the entire novel’s philosophy.
Second, look into other "food-noir" Japanese literature. Authors like Sayaka Murata (Convenience Store Woman) or Han Kang (The Vegetarian) explore similar themes of the body and social rebellion through consumption, albeit in very different styles.
Finally, reflect on your own relationship with "indulgence." The novel suggests that our fear of fat is actually a fear of losing control. Overcoming that fear is the real journey Rika undergoes. It’s not just a book about a killer; it’s a book about the courage it takes to eat a second helping.