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Hereditary Triangle
In the days of their youth, Koutarou Fujiki and Kajiwara were the best of friends. Even the realization that they liked the same girl couldn’t break their bond, and so for years, they both vied for her affection. But that era of Koutarou’s life ended when Kajiwara suddenly left. Now an adult, Koutarou has taken his sweetheart’s hand in marriage, but he’s plagued with doubts—Why did Kajiwara take off? And would his wife, Touko, have chosen differently were he still around? During a visit to their hometown, Koutarou meets someone who sends him hurtling back through his memories...and toward the answer he’s been seeking ever since…
358 pages, Hardcover
Published December 17, 2024
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Displaying 1 - 21 of 21 reviews
November 7, 2025
a slow day read. one of the stories where characters haunt the narrative in a tragically beautiful way. loved.
April 16, 2026
poly could have fixed them
November 27, 2025
Loved this book! Took such an unexpected twist on this triangle love story. I loved how they ended it with you getting answers to your questions.
May 19, 2025
3.5 stars
This was a very calm and low-stakes story and I enjoyed reading it. I liked that it touched upon very familiar and slightly nostalgic feelings, and that it didn't try to be more than it was. It wasn't anything super special or unique, but I enjoyed it for being simple and straightforward.
This was a very calm and low-stakes story and I enjoyed reading it. I liked that it touched upon very familiar and slightly nostalgic feelings, and that it didn't try to be more than it was. It wasn't anything super special or unique, but I enjoyed it for being simple and straightforward.
March 24, 2025
So Koutarou and Touko should have really gotten therapy because I felt so uncomfortable about their interactions with Kaoru. They were putting so much on this college kid.
May 27, 2025
In Summary
Hereditary Triangle is a mature slice of life. Thanks to childhood and college-year flashbacks as well as our college-age character Kaoru, a breadth of lifetime experiences get represented in this standalone story. However, those events tend to be interpreted through the filter of an empty nester questioning the choices he made. While melancholy, it’s also warm and has funny moments with a likable and relatable cast. If you like narratives that are deeply reflective and characters who, despite their weaknesses and hangups, deeply care for one another, give this beautifully produced manga a try.
The Review
Next-door neighbors Koutarou and Tooru grew up as best friends. Their friendship continued even after both fell in love with the same girl. Then one day Tooru left without any explanation. Koutarou wed his sweetheart but has always secretly wondered if his wife would’ve chosen differently if Tooru had stayed. All those doubts come bubbling to the surface decades later when Koutarou returns to his hometown and encounters a dead ringer for Tooru.
Hereditary Triangle involves a relationship triangle, but it’s not your standard love triangle. Usually, the focus is on the feelings of the single female as she interacts with and struggles to choose between the two males fighting for her. In this title, the focus is on Koutarou and Tooru’s shared history, so it ends up feeling like a bromance that gets disrupted when the best friends fall for the same woman.
The book begins with Koutarou and his wife Touko returning to his childhood home to live with his newly widowed mother. That’s when he learns his old neighbor Tooru also recently passed due to an accident. This gets Koutarou thinking about the questions and unresolved feelings when Tooru left. Then things come to a head when he encounters Tooru’s son Kaoru, who’s sorting through his father’s belongings in the house next door.
Kaoru looks exactly like his father in his youth. Hayashi-sensei draws them exactly alike, save for a mole beneath Kaoru’s eye to differentiate the two. Thus, Kaoru serves as a kind of stand-in for his deceased father as Koutarou grapples with decades-old insecurities and the mystery of why Tooru distanced himself so abruptly.
Therefore, this is not an impassioned romance. Even in the flashbacks of Koutarou, Touko, and Tooru’s university years, they are portrayed as a comfortable threesome with Tooru inserting himself as a not-unwelcome third wheel on Koutarou and Touko’s dates. Instead, the plot focuses on Koutarou’s regrets about the way his friendship with Tooru disintegrated and guilt about the happy marriage he got after his friend took off.
The story sticks mainly with Koutarou’s POV, but Touko and Kaoru also get a chance to voice their thoughts. Readers get a frank perspective on Tooru’s and Touko’s thoughts about Koutarou in a recounting of the only “date” Tooru had with Touko at a local aquarium. As for Kaoru, it may seem strange for someone his age to be interacting with friends of his father’s that he never knew. However, Tooru was a bit of a mystery to his son due to the lengthy travels that came with his career as a photographer. Because Kaoru’s interactions with the couple allow him to learn more about his father (as well as get help sorting through his father’s sizable collection of personal effects), the interplay between the three characters is natural and believable.
The artwork is clean, and the characters are easily identifiable in their different stages of life. Illustrations do an excellent job of setting the atmosphere and conveying the varied emotions of the characters.
Extras in this hardcover standalone book include full-color foldout illustration, author afterword, and bonus illustration.
For more manga and book reviews, drop by my blog Keeping It In Canon!
Hereditary Triangle is a mature slice of life. Thanks to childhood and college-year flashbacks as well as our college-age character Kaoru, a breadth of lifetime experiences get represented in this standalone story. However, those events tend to be interpreted through the filter of an empty nester questioning the choices he made. While melancholy, it’s also warm and has funny moments with a likable and relatable cast. If you like narratives that are deeply reflective and characters who, despite their weaknesses and hangups, deeply care for one another, give this beautifully produced manga a try.
The Review
Next-door neighbors Koutarou and Tooru grew up as best friends. Their friendship continued even after both fell in love with the same girl. Then one day Tooru left without any explanation. Koutarou wed his sweetheart but has always secretly wondered if his wife would’ve chosen differently if Tooru had stayed. All those doubts come bubbling to the surface decades later when Koutarou returns to his hometown and encounters a dead ringer for Tooru.
Hereditary Triangle involves a relationship triangle, but it’s not your standard love triangle. Usually, the focus is on the feelings of the single female as she interacts with and struggles to choose between the two males fighting for her. In this title, the focus is on Koutarou and Tooru’s shared history, so it ends up feeling like a bromance that gets disrupted when the best friends fall for the same woman.
The book begins with Koutarou and his wife Touko returning to his childhood home to live with his newly widowed mother. That’s when he learns his old neighbor Tooru also recently passed due to an accident. This gets Koutarou thinking about the questions and unresolved feelings when Tooru left. Then things come to a head when he encounters Tooru’s son Kaoru, who’s sorting through his father’s belongings in the house next door.
Kaoru looks exactly like his father in his youth. Hayashi-sensei draws them exactly alike, save for a mole beneath Kaoru’s eye to differentiate the two. Thus, Kaoru serves as a kind of stand-in for his deceased father as Koutarou grapples with decades-old insecurities and the mystery of why Tooru distanced himself so abruptly.
Therefore, this is not an impassioned romance. Even in the flashbacks of Koutarou, Touko, and Tooru’s university years, they are portrayed as a comfortable threesome with Tooru inserting himself as a not-unwelcome third wheel on Koutarou and Touko’s dates. Instead, the plot focuses on Koutarou’s regrets about the way his friendship with Tooru disintegrated and guilt about the happy marriage he got after his friend took off.
The story sticks mainly with Koutarou’s POV, but Touko and Kaoru also get a chance to voice their thoughts. Readers get a frank perspective on Tooru’s and Touko’s thoughts about Koutarou in a recounting of the only “date” Tooru had with Touko at a local aquarium. As for Kaoru, it may seem strange for someone his age to be interacting with friends of his father’s that he never knew. However, Tooru was a bit of a mystery to his son due to the lengthy travels that came with his career as a photographer. Because Kaoru’s interactions with the couple allow him to learn more about his father (as well as get help sorting through his father’s sizable collection of personal effects), the interplay between the three characters is natural and believable.
The artwork is clean, and the characters are easily identifiable in their different stages of life. Illustrations do an excellent job of setting the atmosphere and conveying the varied emotions of the characters.
Extras in this hardcover standalone book include full-color foldout illustration, author afterword, and bonus illustration.
For more manga and book reviews, drop by my blog Keeping It In Canon!
This entire review has been hidden because of spoilers.
February 26, 2025
*4.5
Hereditary Triangle is a beautiful snapshot of love, regret, and complicated relationships.
This is yet another story about "love triangles" (*love corners really), which usually is not my jam. But I wanted to give this a shot and I'm glad I did, because Hereditary Triangle stands out in its exploration of the complexities of coming to age with a childhood friend. The summary makes it sounds like the plot will focus on the typical angst that you'd get in a love triangle story, but really the plot is more about the internal fear of change. And that is what made me love this manga.
If this were just a story of childhood friends turned bitter rivals over romance, it would blend into the thousands of others just like it. But instead, these are three friends that genuinely love each other, even as they grow apart. Fumiya Hayashi does a fantastic job conveying the complicated emotions behind these three characters as the nature of their relationships change. Kajiwara and Koutarou love each other, they hurt each other, and there is a connection that can't be broken even when they leave each other's lives.
I have to say, as much as I did enjoy reading this, I think the summary is a little misleading. But I guess that wasn't really the point of the story.
The actions and decisions of each character makes sense for who they are as people. The art is beautiful and clean. And the dialog feels realistic.
I love and hate bittersweet stories, and they are always impactful. I love the themes of change (fearing and accepting it), regret, love, and I love the way the story depicts the ways people change our lives, even through memories.
Hereditary Triangle is a beautiful snapshot of love, regret, and complicated relationships.
This is yet another story about "love triangles" (*love corners really), which usually is not my jam. But I wanted to give this a shot and I'm glad I did, because Hereditary Triangle stands out in its exploration of the complexities of coming to age with a childhood friend. The summary makes it sounds like the plot will focus on the typical angst that you'd get in a love triangle story, but really the plot is more about the internal fear of change. And that is what made me love this manga.
If this were just a story of childhood friends turned bitter rivals over romance, it would blend into the thousands of others just like it. But instead, these are three friends that genuinely love each other, even as they grow apart. Fumiya Hayashi does a fantastic job conveying the complicated emotions behind these three characters as the nature of their relationships change. Kajiwara and Koutarou love each other, they hurt each other, and there is a connection that can't be broken even when they leave each other's lives.
I have to say, as much as I did enjoy reading this, I think the summary is a little misleading. But I guess that wasn't really the point of the story.
The actions and decisions of each character makes sense for who they are as people. The art is beautiful and clean. And the dialog feels realistic.
I love and hate bittersweet stories, and they are always impactful. I love the themes of change (fearing and accepting it), regret, love, and I love the way the story depicts the ways people change our lives, even through memories.
May 22, 2025
Wow, solid 3.5 story that almost made me cry.
This is a beautiful take on a “love triangle”. Seeing someone who looks just like your friend who recently passed would indeed be shocking. It’s even more shocking to learn that he’s your friend’s child.
The mystery surrounding why he left was done so well and actually made emotional. None of them wanted to hurt the other but he ran to avoid getting left behind. Using flashbacks and the shared love of photography between the father and son was adorable. I’d definitely recommend this as a light hearted read.
Thanks to Edelweiss and Yen for the DRC.
This is a beautiful take on a “love triangle”. Seeing someone who looks just like your friend who recently passed would indeed be shocking. It’s even more shocking to learn that he’s your friend’s child.
The mystery surrounding why he left was done so well and actually made emotional. None of them wanted to hurt the other but he ran to avoid getting left behind. Using flashbacks and the shared love of photography between the father and son was adorable. I’d definitely recommend this as a light hearted read.
Thanks to Edelweiss and Yen for the DRC.
July 19, 2025
Saw this book at the library and picked it up. It's a slice of life love triangle story but more adult. I really like how the shoujo genre and the slice of life genre have evolved for more mature audiences like 5 Centimeters Per Second. I did enjoy this book. But felt parts were drawn out and we never really got to see the story from the other side. However that is intentional as the pov is that of an old friend trying to figure out the past in relation to the present. Overall I might bump this up to 4 stars if it lingers on in my mind for a couple of days.
June 27, 2025
I’m not sure how this was really a mystery and it was a very underwhelming conclusion. Everyone acts childish and immature and the two main characters are still hung up on their ex friend from decades ago. Maybe it’s just a cultural thing, but it just seemed like two adults who never moved past college in a weird way and then treat their friend’s child super weird. The writing/translation and art aren’t bad (except the zoo animals) but the story just didn’t do anything for me.
January 23, 2026
This was really nice. As the title suggests, there's a bit of a love triangle, but it's more about longing and melancholy for a happy past than drama. I wasn't sure at first if it was going to go somewhere uncomfortable, but it didn't, and in fact wrapped up very well. The artwork is pleasant and evocative; a number of scenes have plants giving shade to the character and I love the effect. Very summery feel (which is lovely on a subzero day).
May 7, 2025
WTF.
I don't know what you think you've won, kid, but this isn't a healthy thing.
Kajiwara did the right thing by getting himself put of there.
Koutarou and Touko need A LOT of therapy.
Koutarou, you've been married for how long? Why are you like this?
Touko, wtf are you doing?
Seriously, Kajiwara was SO RIGHT to get away from there.
I don't know what you think you've won, kid, but this isn't a healthy thing.
Kajiwara did the right thing by getting himself put of there.
Koutarou and Touko need A LOT of therapy.
Koutarou, you've been married for how long? Why are you like this?
Touko, wtf are you doing?
Seriously, Kajiwara was SO RIGHT to get away from there.
October 11, 2025
A really heartfelt one shot. It's not a tearjerker but I felt myself getting sad for the characters and understanding how they must have felt without the story being overdramatic. It's a quiet sort of nostalgic sadness, that comes from deep within the soul.
March 26, 2025
Not sure why this book got such a low rating. I loved it, it really makes you think about life and how things change and how to deal with that.
July 15, 2025
Really good book
August 11, 2025
At first I felt the translation felt off and I was trying to patiently see where it was going. I was touched and crying by the end.
August 12, 2025
Was i hoping for more drama? Yes. Was i still deeply satisfied with the ending and emotional depth of the characters? YES!
Read
January 7, 2026Interesting take on the love triangle trope. Problem could have been solved if they just became a polycule though lol
January 24, 2026
3.5
interesting and moving, but also heartbreaking. I do love that Kaoru called them both out cause yeah, they were kinda stupid. But, ah, young love.
interesting and moving, but also heartbreaking. I do love that Kaoru called them both out cause yeah, they were kinda stupid. But, ah, young love.
January 30, 2026
3.5 stars
July 23, 2025
Really enjoyed this title. The characters were excellent. At first, I was bothered by the couple and how they seemed to dump their guilt on kajiwara's son. But by the end, I figured that the son also got some sort of closure and family extension. The author's note was also helpful in understanding this concept of a triangle.
Displaying 1 - 21 of 21 reviews