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Hybrid Heart
A pop idol in near-future Japan. Her every move controlled in the present and haunted by the past.
The stage is the surveillance society of near-future Tokyo. In order to become an idol, Rei has sacrificed her private life as she focuses on her solo activities. Haunted by guilt, the insidious manipulations of a controlling talent manager, and the corporate bioapps colonizing her body, Rei must find a way to reclaim her discarded anonymity and autonomy within a cyberpunk society where Vocaloids and V-singers flourish.
The stage is the surveillance society of near-future Tokyo. In order to become an idol, Rei has sacrificed her private life as she focuses on her solo activities. Haunted by guilt, the insidious manipulations of a controlling talent manager, and the corporate bioapps colonizing her body, Rei must find a way to reclaim her discarded anonymity and autonomy within a cyberpunk society where Vocaloids and V-singers flourish.
122 pages, Kindle Edition
Published March 28, 2023
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Displaying 1 - 29 of 29 reviews
September 10, 2025
2*s for me. Just not in my reading zone. I had to work to finish it. The abusive relationship between the manager and Rei was very painful to read about.
February 25, 2025
Hybrid Heart is the light novel version of a feminist, Japanese psychological thriller but executed very well and communicates its ideas clearly. Rei is a pop idol whose life has become a nightmare and it’s making her crazy. Always smiling and hyper cheerful, she does the choreography, and hits the notes. Her face is on magazines everywhere, but she is isolated, anorexic, and constantly blaming herself. Her manager is a psycho and, oh it’s the future, and she has a control chip implanted in her. It’s a darkly funny and chilling portrayal of abuse, but then it kind of holds your hand on a healthy way to process all this with blandly positive end. It’s a pretty transparent metaphor for problems teenage girls face, but as a light sci fi thriller. Audiobook read by Sarah Skaer is very good.
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January 2, 2025First book of the year! Compelling Neon Hemlock novella about a Japanese idol singer and pop star, and the whole-body control her production company have over her. Disturbing and very good, and the main character is really well drawn.
February 23, 2025
3.5⭐
As an idol fan, I find this deeply upsetting and depressing. In a good way.
As an idol fan, I find this deeply upsetting and depressing. In a good way.
April 8, 2023
An excellent examination of a human being struggling to maintain a glittering persona and the career it gives her. Having lost her best friend and singing partner to scandal, Rei lives a horrifically lonely and micromanaged life; neural implants ping her company to rat her out for sleeping too little or eating too much. Almost all of her relationships are now parasocial. Her fear of losing her career is almost stronger than her fear of losing herself...until a fresh new face arrives, and Rei watches the cogs of the idol machine prepare to grind someone else down, turn a girl into a doll. Fascinating, frightening, and all too real.
July 30, 2024
picked this up because of the quote on the back that said “this book fucks extremely,” and i simply must agree. i really liked how it felt like it reflected what i know of modern idol culture, enhanced by the sci fi elements like the main character’s neuro implants that monitored her calorie intake and such. very emotional and vivid and i appreciated the realistically hopeful ending!!
October 28, 2023
Updated from 4 to 5 stars because I am still thinking about this book on a weekly basis.
An upsettingly good depiction of abuse, especially with the slight sci-fi angle, and a ruthless interrogation of the idol industry. I wish there was a little more at the end, and it would have been nice to actually know some of the song lyrics, but the ending is still very solid and an author is not necessarily a songwriter!
An upsettingly good depiction of abuse, especially with the slight sci-fi angle, and a ruthless interrogation of the idol industry. I wish there was a little more at the end, and it would have been nice to actually know some of the song lyrics, but the ending is still very solid and an author is not necessarily a songwriter!
February 7, 2026
I loved this. A scathing critique of the idol industry, a meditation on disordered restrictive eating, with hints at a lost romantic love between Rei and Ririko, this novella is one of the best things I've read about the idol industry (and that's as someone who quite critically enjoys idol anime) and one of the best stories about disordered restrictive eating I've read in a while.
Some notes about the work:
-Rei's abuse by her manager Kosaka, in a more middling or poorly written work, could've framed Kosaka in a sympathetic or romantic light. I'm genuinely glad Iori Kusano didn't go that way, because I know a lot of authors would've made Kosaka sympathetic in some way, or as secretly in love with Rei or something. It's actually much more realistic, and more stark of an image, for Kosaka to be doing these things as a twisted way to get control over women, and could be a wider metaphor for how, like producers rule over their idols with an iron fist, men will try to control and take advantage of women and the gender marginalized to feel any sense of control in their lives.
-I actually like how, in the end, Rei creating her VTuber avatar ZERO ended up being freeing for her rather than another tool of control and misogyny. While the misogyny of these sorts of software that people use to create VTuber avatars is a reality that an animation designer calls out earlier in the novel at that point, Rei ends up using the technology to take back her freedom and design her avatar as a realistic depiction of herself. I love the way technology and avatar design intersects with the self, and this is another piece of media I appreciate that has done things with it.
-Rei's weight gain at the end isn't depicted as disgusting or bestial like in a similar novel I read, failure to comply; rather, Rei's weight gain is accepted as an anxiety inducing part due to the way her eating disorder works and how Kosaka had groomed her into hating her body, but also as a comfort and a metaphor for freedom after being restricted for so long. I really liked that aspect of the story. Less stories where weight gain is depicted as monstrous, more stories where weight gain is framed as healing and life saving, especially if a person gets fat because fatness is not a death sentence and fat people are worthy of life.
-The writing style is so intriguing; I'm fond of the scenes in the book that jump to events in the present, then events in the past with Ririko and Rei. The change from flashbacks to the past as Rei quits being an idol, too, is also a neat choice as it shows Rei has moved on from Ririko's disappearance, even if she still misses her.
Some notes about the work:
-Rei's abuse by her manager Kosaka, in a more middling or poorly written work, could've framed Kosaka in a sympathetic or romantic light. I'm genuinely glad Iori Kusano didn't go that way, because I know a lot of authors would've made Kosaka sympathetic in some way, or as secretly in love with Rei or something. It's actually much more realistic, and more stark of an image, for Kosaka to be doing these things as a twisted way to get control over women, and could be a wider metaphor for how, like producers rule over their idols with an iron fist, men will try to control and take advantage of women and the gender marginalized to feel any sense of control in their lives.
-I actually like how, in the end, Rei creating her VTuber avatar ZERO ended up being freeing for her rather than another tool of control and misogyny. While the misogyny of these sorts of software that people use to create VTuber avatars is a reality that an animation designer calls out earlier in the novel at that point, Rei ends up using the technology to take back her freedom and design her avatar as a realistic depiction of herself. I love the way technology and avatar design intersects with the self, and this is another piece of media I appreciate that has done things with it.
-Rei's weight gain at the end isn't depicted as disgusting or bestial like in a similar novel I read, failure to comply; rather, Rei's weight gain is accepted as an anxiety inducing part due to the way her eating disorder works and how Kosaka had groomed her into hating her body, but also as a comfort and a metaphor for freedom after being restricted for so long. I really liked that aspect of the story. Less stories where weight gain is depicted as monstrous, more stories where weight gain is framed as healing and life saving, especially if a person gets fat because fatness is not a death sentence and fat people are worthy of life.
-The writing style is so intriguing; I'm fond of the scenes in the book that jump to events in the present, then events in the past with Ririko and Rei. The change from flashbacks to the past as Rei quits being an idol, too, is also a neat choice as it shows Rei has moved on from Ririko's disappearance, even if she still misses her.
This entire review has been hidden because of spoilers.
November 10, 2023
She could tell Aimi it gets easier, but that would be a lie. The better Rei gets, the less she satisfies anyone, herself included. There is always a more challenging song looming on the horizon. All success does is raise the bar higher. But if Aimi is anything like Rei she will feed off this. She will live for it. Rei suspects that people who know how to be satisfied with themselves don't become idols.
Setting:
This book takes place in near future Japan.
Character:
Rei: Rei is an 'idol' which essentially just means pop star. She is famous for her singing and dancing. Rei has worked extremely hard to get and maintain this life and given up pretty much everything else that could have been in her life.
Plot:
Being an idol had grown increasingly difficult for Rei. Part of the issue is the increasing popularity of digital avatars used by signers, essentially vtuber signers (think Hatsune Miku). The other part of the issue is that Rei is finding it harder and harder to tolerate the terrible working conditions (and living conditions) imposed by her extremely controlling manager.
My Thoughts:
This book is, for the most part, rather depressing. Rei has a pretty objectively terrible life that she has sort of mentally tricked herself into thinking she likes but it's getting hard for her to keep that fantasy going. Every aspect of her life, what she eats, how much she sleeps, what she does online is monitored by her manager who demands she spends nearly every waking moment working herself to death to be a perfect idol for consumption.
It's easy to look at the life of a movie star or famous musician from the outside and think that the cheering crowds and adoring fans must be wonderful, and to some extent, I'm sure they are. But there's a lot of difficulty the crowd doesn't see; that the crowd is very specifically not supposed to see. You're not supposed to see the 150 takes it took to get the perfect shot of the action hero doing the triple backflip while perfectly throwing knives at five different enemies. This story focuses on that and dials it up to eleven by having Rei have things like a calorie counting device installed in her body that warns her anytime she eats something that might threaten her perfect figure.
Given the book's very limited page count there isn't a lot more that I can say with spoiling things. I do think it's well written and does a good job of telling the story it's trying to tell but unless you want to be bummed out or get a peek at what the entertainment industry's dirty laundry might in theory look like, it's sort of hard to recommend.
Setting:
This book takes place in near future Japan.
Character:
Rei: Rei is an 'idol' which essentially just means pop star. She is famous for her singing and dancing. Rei has worked extremely hard to get and maintain this life and given up pretty much everything else that could have been in her life.
Plot:
Being an idol had grown increasingly difficult for Rei. Part of the issue is the increasing popularity of digital avatars used by signers, essentially vtuber signers (think Hatsune Miku). The other part of the issue is that Rei is finding it harder and harder to tolerate the terrible working conditions (and living conditions) imposed by her extremely controlling manager.
My Thoughts:
This book is, for the most part, rather depressing. Rei has a pretty objectively terrible life that she has sort of mentally tricked herself into thinking she likes but it's getting hard for her to keep that fantasy going. Every aspect of her life, what she eats, how much she sleeps, what she does online is monitored by her manager who demands she spends nearly every waking moment working herself to death to be a perfect idol for consumption.
It's easy to look at the life of a movie star or famous musician from the outside and think that the cheering crowds and adoring fans must be wonderful, and to some extent, I'm sure they are. But there's a lot of difficulty the crowd doesn't see; that the crowd is very specifically not supposed to see. You're not supposed to see the 150 takes it took to get the perfect shot of the action hero doing the triple backflip while perfectly throwing knives at five different enemies. This story focuses on that and dials it up to eleven by having Rei have things like a calorie counting device installed in her body that warns her anytime she eats something that might threaten her perfect figure.
Given the book's very limited page count there isn't a lot more that I can say with spoiling things. I do think it's well written and does a good job of telling the story it's trying to tell but unless you want to be bummed out or get a peek at what the entertainment industry's dirty laundry might in theory look like, it's sort of hard to recommend.
July 14, 2024
One of the best ways I think I can describe this book is by saying it feels complimentary to another title I read recently A Magical Girl Retires . Both of these titles take these two fantastical elements of entertainment, magical girls and idols, and layers on the harsh reality of what is actually like to be one of those girls. (Well as real as a magical girl is in this reality or the next). There is just something so raw and glaring about these two books that really just makes you reflective of how terribly women and girls are treated in media.
This story is, as I thought throughout while reading, incredibly dystopian. But in a way that is incredibly reflective of our current reality. For the most part, there are dystopian future bits of technology but they are not as centralized as the bits of technology that as far as I can tell are based on real things. Because both singing behind avatars and virtual idols are basically no name-brand ways of describing V-tubers and Vocaloids. Which in reality, at this point in time, are not mechanisms of evil out to get real flesh and blood idols but I feel like that is also part of the lesson that the MC had to work through.
Overall I would say this is a slightly lighter read that A Magical Girl Retires but it still does a great job at highlighting a similar vein of our troubled reality.
This story is, as I thought throughout while reading, incredibly dystopian. But in a way that is incredibly reflective of our current reality. For the most part, there are dystopian future bits of technology but they are not as centralized as the bits of technology that as far as I can tell are based on real things. Because both singing behind avatars and virtual idols are basically no name-brand ways of describing V-tubers and Vocaloids. Which in reality, at this point in time, are not mechanisms of evil out to get real flesh and blood idols but I feel like that is also part of the lesson that the MC had to work through.
Overall I would say this is a slightly lighter read that A Magical Girl Retires but it still does a great job at highlighting a similar vein of our troubled reality.
May 24, 2023
I backed the Neon Hemlock novella series for 2023, and this was in my first package! This was one of the ones that caught my attention, as the summary indicated that this was about an idol in near future Japan, and combining the already surreal/exploitative world of idols in Japan with digital surveillance/the panopticon seemed like a fun vaguely nightmare inducing scenario already. But add in cyberpunk, a controlling/abusive manager who uses the apps that Rei has to install per her contract, and another younger girl coming down the pipeline, and you have an A++ premise. I do wish it had leaned a bit more into the sapphic vibes I got from it, but honestly, that is my only piece of criticism. Also, Not Vocaloids! It's fantastic to watch Rei decide how much of herself she's willing to give over, and when and how she inevitably decides to push back. This is Kusano's debut novella, and to quote Isabel Kim on the back cover, "this story fucks extremely". Pick it up, you're going to be hearing about this novella and Kusano come awards time, I think.
May 12, 2024
2.5 rounded up? 3? Something like that.
I don't have that much to say about this. I mean... I think I may just not be the target audience as someone already familiar with idol culture. I'm happy Rei got her freedom back but ultimately this book felt kind of like a whole lot of "okay, and then?" to me. Idol culture is deeply oppressive. We know that... okay, that's it, I guess. The Ririko and Lyrico plot felt kind of like it went nowhere too.
Not gonna say it's a waste of time because it's so short, but yeah. Feels like it may work better as some kind of manga one-shot than a novella.
I don't have that much to say about this. I mean... I think I may just not be the target audience as someone already familiar with idol culture. I'm happy Rei got her freedom back but ultimately this book felt kind of like a whole lot of "okay, and then?" to me. Idol culture is deeply oppressive. We know that... okay, that's it, I guess. The Ririko and Lyrico plot felt kind of like it went nowhere too.
Not gonna say it's a waste of time because it's so short, but yeah. Feels like it may work better as some kind of manga one-shot than a novella.
June 12, 2024
An interesting commentary on idol culture and societal subjugation of the female body, but not a book I’m hooked on. I did like the narrative choice to juxtapose Rei’s current life with memories of her and Ririko, but I still never felt like I could connect the two emotionally. Ririko felt like a vague idea of a character (and I get the book was like barely 100 pages so I won’t fixate on that too much) that didn’t serve as a foil as strongly as I think she was intended to. The addition of Aimi to the story I think definitely added to the momentum with Rei being forced to confront her own abuse and complicity in the cycles. Again, a cool book idea, but just not one I found super compelling.
April 30, 2023
I don't think I'm interested in pop idols, although this is the second book I've read about them, so perhaps I am. I enjoyed the near-future extension of everything that's wrong about pop stardom and girls' self-image generally. Rei's recovery of her autonomy took a form I wasn't expecting, and I found that interesting. The danger, of course, of reading a novella on an e-reader is that the end sneaks up on you before you're ready, which may be the reason I wish that Rei's relationships with Aimi and with Ririko were explored more thoroughly.
February 28, 2024
I wasn't sure what to expect with this one; it wasn't on my radar at all until I saw it on several recommended reading lists for sci-fi awards season. I also am not really a fan of K-pop, J-pop, or any type of pop music frankly. But I found this to be a brilliant character study of a young woman who was thrust into the spotlight too early and isolated from any outside influences that would have counteracted the abuse of her manager. I was rooting for her the whole way through, and this will definitely be going on my Hugo nomination ballot this year.
April 27, 2023
Paranoid novella about near-future Japanese idol stardom and the horrific ordeals of existing in a body whose every action is tightly monitored and controlled for brand preservation. Kusano writes the pain of scrutiny, fear, anorexia and exacting beauty standards very well. As with a lot of dystopian SF this is merely an exaggeration of existing structures of power and domination, and exploring the manufactured J- / K-pop idol industry works pretty well here.
July 15, 2023
This was a satisfying evening read. I was particularly interested because I've messed around with vocaloids and AI and such, and as portrayed in the book, that's not really a central or speculative element of the story. It's more about the way Rei's existence is monitored and manipulated, inside and out (though it doesn't dwell on the body-horrific aspects of that), and how she handles that--how what she's willing to endure that for changes.
July 26, 2023
I went into this story expecting science fiction, cyberpunk maybe. Alas, what I got was misery. It is interesting - insofar as witnessing someone caught in a trap constructed in their mind can be an exposure of evil practices - but certainly not the entertainment I wanted.
I ended giving up on it after about a quarter in.
I ended giving up on it after about a quarter in.
February 12, 2024
I reached the end of this feeling… unresolved. Rei’s story has a nice rounded arc and I think was handled really well, but there were some trailing ends that I think could have been more deliberately concluded: namely Ririko and Lyrico. Obviously we as the audience realize some things that Rei might not catch on to, but still wanted more resolution there.
November 13, 2025
Excellent writing with very difficult subject matter. The exploration of its themes of pop idols, privacy, control, bodily autonomy, and what of yourself is worth putting into your work made for a very reflective, if stressful, book. I liked the ending, which was a quieter success than I expected, but I think that suited this particular story.
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July 14, 2023Review to come, soon IY"H (I already wrote it, but I still need to schedule both the Patreon version and the free version for later)
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Source of the book: Lawrence Public Library (who ordered it on my request, thank you!)
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Source of the book: Lawrence Public Library (who ordered it on my request, thank you!)
December 13, 2024
HYBRID HEART by Iori Kusano is short, poignant, powerful, & timely. A near future sci-fi novella that offers a window into the life of a Japanese pop idol, this story is atmospheric & chilling. Short & sharp, it inspired Solo Act, a pastel pink highball.
https://www.youtube.com/watch?v=fFJS1...
https://www.youtube.com/watch?v=fFJS1...
April 22, 2025
A short but interesting story about abusive relationships. Light elements of sci-fi that don't really play too much into the story but are nonetheless core to the story. I wasn't sure I would care about an idol story when I picked this audiobook blind from a virtual pile but I'm glad I did.
April 6, 2023
Unbelievably good.
March 14, 2024
So different than I expected but beautifully well written story of fame/glory and the abuse that comes with it
October 5, 2024
Quick read. Kpop is not my thing but i liked this book
February 28, 2024
In a near-future world of body-mod electronics and virtual entertainment, mid-career idol Rei struggles with the absconding of her former duo partner, her abusive relationship with her manager, the struggles of guiding a novice idol toward a better life, and her own internalization of the wretched system she works in.
Iori Kusano's novel is deliberately written, using its sci-fi trappings to reflect less on matters of material technology, than on the ways technology is deployed by societal forces. The figure of Rei--an idol who, in a Faustian bargain of the body, has contorted herself into the perfect idol--brings up hard questions about the tradeoffs we're willing to make, enabled and aggravated by technology. It applies not just to idols, but to anyone who internalizes the algorithms that run our hybrid world, and painstakingly conform to them to reach some desired outcome: fame, adoration, success. That said, it's especially poignant for anyone who's worked in a career of passion-driven exploitation: as the novel unflinchingly shows, passion in the abstract is never extracted without real, physical costs to the physical body.
While I understand why it's written as it is, I nonetheless wish this novel hadn't been so solipsistically confined Rei's mind. It's a very subjective take, with little time taken to really hash out scenes or ground the reality of other characters. It's also got a thick coating of what I can only call "workshop gloss", which in my opinion works against the kind of stark, genre work it's trying to achieve.
Iori Kusano's novel is deliberately written, using its sci-fi trappings to reflect less on matters of material technology, than on the ways technology is deployed by societal forces. The figure of Rei--an idol who, in a Faustian bargain of the body, has contorted herself into the perfect idol--brings up hard questions about the tradeoffs we're willing to make, enabled and aggravated by technology. It applies not just to idols, but to anyone who internalizes the algorithms that run our hybrid world, and painstakingly conform to them to reach some desired outcome: fame, adoration, success. That said, it's especially poignant for anyone who's worked in a career of passion-driven exploitation: as the novel unflinchingly shows, passion in the abstract is never extracted without real, physical costs to the physical body.
While I understand why it's written as it is, I nonetheless wish this novel hadn't been so solipsistically confined Rei's mind. It's a very subjective take, with little time taken to really hash out scenes or ground the reality of other characters. It's also got a thick coating of what I can only call "workshop gloss", which in my opinion works against the kind of stark, genre work it's trying to achieve.
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February 10, 2025A glittery trap that snaps shut the moment you read the opening page. I couldn't put this one down, mostly because the book wouldn't let me. I am only now starting to breathe normally. A visceral fictional account of a too-plausible dystopia.
August 31, 2023
This is such a fresh cyberpunk story, I’ll never think about the subgenre the same way!
Displaying 1 - 29 of 29 reviews