Decomposition Book: A Novel

by Sara van Os

An emotional, electrifying, and darkly hilarious debut about a woman who finds a dead body and can’t give up its ghost, for fans of Mona Awad, Yellowjackets, and weird girl fiction.

Spiraling from a disastrous falling-out with her best friend, Savannah retreats to her parents’ empty lake house in upstate New York to tend her wounds. Isolated and reeling from rejection, she spends her days in a fog, drinking and overthinking in equal worrisome measure. Until she wakes up one morning in the woods behind the house—next to a dead body.

Instead of calling the police, Savannah reads the journal she finds nearby, reliving the last desperate months of this woman’s life lost in the wilderness, fighting for survival. Ava, as it turns out, is more than just a cold, lonely corpse. She was funny. She was smart. And Savannah has finally found someone she can talk to…

As she pushes deeper into Ava’s harrowing story, Savannah notices a change, a shift in her reality. Each page brings her closer to the Ava from the journal…and the ghost before her now. Before long, Savannah feels something for Ava she hasn’t felt for anyone else—and there’s a good chance letting go would haunt her for the rest of her life.

Is Savannah finally losing her grip? Or has she found the friend she’s needed all along?

Genres: Horror, Queer, Lesbian, Adult, LGBT, Fiction, Contemporary

320 pages, Hardcover

Expected publication May 19, 2026

Reviews

[luceski · Rating 5 out of 5]

Nothing says “self‑care” like waking up beside a corpse and accidentally gaining a free therapist.

Decomposition Book is one of those stories that sneaks up on you - darkly funny, deliciously descriptive and quietly devastating. It opens with a hike gone wrong and spirals into a reality‑bending duet between Ava (who is very much decomposing) and Savannah - who is very much not okay.

Two POVs, two unraveling minds and one emotional‑support corpse she definitely didn’t sign up for.

Savannah’s intrusive thoughts? Relatable. The way their realities start to blur and intertwine? Chef’s kiss chaos.

If you like your fiction a little weird, a little tender, and a little decomposing around the edges… this one’s for you!

[Clara Gauthier · Rating 5 out of 5]

This is THE novel for fans of Yellowjackets, especially if you’re looking for homoerotic hauntings, a compelling survival narrative, lesbian repression, and mentally ill young woman coping.

Von Os’s stunning debut follows Savannah, a 21 year old on a semester off collage due to a dramatic fall out with her manipulative ex-best friend currently staying at her mom’s house in the woods. Her days consist of her waning away the hours until she can take her Ambien at midnight, usually by self-medicating with wine, until after one night of mixing the two when she wakes up next to a dead girl, Ava, in the forest. However, Savannah can’t make herself report the body. She makes herself a promise: she’ll call the cops about the body when it is fully decomposed, taking the time in between to read the mysterious journal left behind.

I was obsessed with both perspectives in this novel, especially Ava’s. Van Os’s prose is spectacular and she conveys such feeling in her imagery. This novel also has lots of brilliant lesbian feelings, both sad and sweet, that just really made me love it all the more. Definitely more atmospheric than scary, but not a bad thing when done well, which this one definitely does! I can’t wait for May when I can shove the physical version into everyone’s hands. Thanks to Netgalley and HarperCollins for the ARC!!

[Erin Larson-Burnett · Rating 2 out of 5]

To put it as eloquently as I can, this book is a major cringefest and not the good kind

[saturnn · Rating 2 out of 5]

i’ve been given the opportunity to receive this arc in exchange of an honest review: i planned to dnf this however i wanted to see it out and i ended up reading it all

honestly at first i was hooked and then it got fever dream heavy. i liked savannah and there were certain lines that hit home especially when she’s kind of announcing how lonely she feels, however she annoyed me really quick i didn’t really see a point in her perspective anymore after a few chapters she just felt so annoying & pointless.

i enjoyed the writing within Ava’s story and how she wrote her life within the journal it was an interesting plot line that i don’t think i’ve seen done before.

the writing was not bad but it also was not the best…why are we mentioning “looking at the solar eclipse like trump”, “scrolling on Tiktok” “WAP by cardi B” and so much more it just felt disappointing reading i literally couldn’t do anything other than eye roll it did not belong in the book whatsoever there are so many analogies that could’ve been used also trigger warning a phrase using the word “r*pist” was used when michelle had put her legs on savannah early on no idea why ?? but was uncomfortable after there was like no reason what so ever to put that line there.

the writing with ava though again was good! she was the only plot and character i liked in the sense of writing it flowed it was fast & it didn’t feel like a bore to get through.

the story then just got weird out of nowhere, it felt like one of those horror lit fic books kinda like bunny..but the opposite where you literally don’t know what you’re reading anymore because so much is happening and so much rambling is going on.

savannah has some sort of illness and sees her ex bestfriend michelle someway somehow? she’s obsessed with death and at some point starts talking to you the reader (i really got confused here bc it happened outta nowhere). i honestly don’t even know how to explain her character 3

i’m sad this book wasn’t as good as i hoped the plot had so much potential but i hope others enjoy it more than i did & wishing the author best of luck in their next !!

thank you to harper collins / harlequin trade publishing for the ARC in exchange for an honest review !

[Sammantha (its_a_literary_life) · Rating 4 out of 5]

This one completely caught me off guard in the best way! This debut left me feeling somber and empty and I think speaks volumes for mental health, trauma, grief, and surviving yourself.

Van Os dives headfirst into the morbid and the metaphorical. Savannah, staying at her parents isolated vacation home and healing from personal trauma, wakes up beside a dead body in the woods, and instead of reporting it, she proceeds to read the departed woman’s journal while the corpse literally decomposes in the forest. What ensues is a strange, uneasy blend of psychological introspection, queer longing, and creeping unreality.

Healing is not linear and I think this book shows that. It’s cyclical and messy.

I will say in the beginning I was more intrigued with Ava's story but as the story developed I kept thinking about what was real and not through Savannah's perspective. The blurb says this is "darkly humorous" and I find the eggshell sharp humor here to be far and few.

The lake front setting is both isolated but seemingly beautiful in spite of the decaying corpse in the woods. Idk but the cover is even beautiful in a morbid way in my opinion. I was both creeped out and emotionally moved with the story by the end.

The queer representation and self destruction is seen from both perspectives. I found Savannah to be almost wallowing in self pity until I found out what happened between her and Michelle.

It's told in alternating perspectives from Savannah in the present to Ava's past and what led her to her death and I think it kept the story moving forward nicely.

There’s something genuinely affecting about the way loneliness, grief, and queer desire get woven through surreal horror.

If you are a fan of weird girl fiction, Yellowjackets, and Mona Awad’s brand of unsettling, genre-blurring storytelling, you HAVE to pick this up.

4.5 stars

[Brittany K · Rating 5 out of 5]

Darkly hilarious, entirely too relatable (besides the corpse hoarding, of course) and utterly heart wrenching- Decomposition Book is for those of us who can’t resist some weird girl fiction!
Oh, the corpse hoarding? Yea, I guess I should explain that part.
I didn’t expect a story about a girl who wakes up next to the body of a deceased hiker and does *not* call the cops but instead chooses to visit the dead body while reading the said hiker’s journal to tug my heartstrings so much. But alas, this book has wormed its way right into my heart.
Now I know that sentence sounded insane, but our main character Savannah is precious to me. She’s incredibly lonely, a little lost, probably losing it, and has the most relatable OCD intrusive thoughts and inner monologue I’ve ever read.
As Savannah reads Ava’s Decomposition Book detailing her time lost in the woods, Ava becomes more than just a corpse and almost like the friend she so desperately needed; making it even harder to let her go.
I love this book with my whole heart and totally understand it won’t be for everyone, but it was definitely meant for me 🫶🏻

[Courtney · Rating 4 out of 5]

If you like the show Yellowjackets, you should definitely give Decomposition Book a read!
Savannah is taking time off from college for a mental health reset - time with nothing to do but watch movies, avoid the obsessive compulsive thoughts, and take a walk in the woods.
One morning she wakes outside with no recollection of how she got there - or how the deceased body next to her is there. After deciding to allow decomposition to take place before reporting the body, Ava begins to investigate. What she’s unsure of throughout the novel is: has she officially lost ties to reality?

I really enjoyed the premise of the book since it’s truly unlike anything I’ve ever read. Savannah and Ava were both strong characters so I didn’t find myself rushing through either POV to get back to the other as soon as possible. A strange, unique, heartfelt, and humorous- a psychological thriller addressing themes much deeper than “who dunnit“?

[Siobhan · Rating 4 out of 5]

Decomposition Book is a novel about two young women brought together when one of them finds the dead body of the other. Ava went on a camping trip with two coworkers that didn't go as planned, and never came back. Savannah is staying in her parents' lake house in Upstate New York, reeling from a mental breakdown caused by an incident with her best friend and trying to treat her OCD with not always ideal coping mechanisms. When Savannah mixes a bottle of wine with Ambien, she wakes up next to a dead body: Ava's. And next to Ava's body is a notebook filled with the story of her trip, so Savannah starts to read, and realises Ava might be the girl of her dreams.

This novel is definitely the sort of weird fiction that will work for some people and not for others. Personally, I didn't really know what to expect from it going in, so I was pleasantly surprised by how dark it got. It is a novel that is both a queer survival in the wilderness story and a literary fiction exploration of someone with OCD, brought together through the wild plot line of finding a dead body in the woods and wanting to spend more time with that person.

The narrative is split between Ava's notebook recounting her time in the wilderness and Savannah's perspective, carefully timed so you find out things about Ava around the same time Savannah does in the story. This means that it feels fairly well balanced between them, though initially Ava's story is more gripping so I did find myself looking forward to those sections. However, as Savannah's side develops and you see more of how OCD is affecting her in different ways (for example, in her exploration of her sexuality), then that also becomes more engrossing. I wondered how the book could end given Savannah's fears about what would happen to her when it is discovered that she is hoarding a dead body, but I think that the ending is probably an effective way to focus more on the characters than having a narrative with lots of twists and turns.

I didn't know that this book was about queer characters and OCD before going into it, and that would 've been even more of a selling point for me. Nevertheless, I'm glad that I did choose to read Decomposition Book, for the fascinating way it combines its two narratives and how it makes them weird in a satisfying way.

[Katrina · Rating 2 out of 5]

On a mental health break from college, after a massive falling out with her former best friend, Savannah retreats to her parents’ empty lake house in upstate New York.

On a drunken, medicated walk through the woods, Savannah literally stumbles over the corpse of a missing woman named Ava. True to her mental state, rather than call the police, she reads the dead woman’s diary instead. Finding Ava relatable, funny, and a voice that cures her loneliness, Savannah decides to keep her discovery a secret.

The novel switches viewpoints every so often, from Savannah’s internal chaos to the words recorded in Ava’s diary, and I have to say I found Ava’s story infinitely more compelling, even if I had to suspend disbelief slightly about her predicament.

Savannah held my attention in the first couple of chapters, but she quickly became unlikable — and, worst of all, uninteresting. Certain revelations from her past made me sympathetic, but they never made her character compelling, and I couldn’t connect with her beyond that.

My own niggles aside, this was still a promising debut, and while the book didn’t quite land for me personally, after reading the other reviews it really is a minority opinion.

I’m sure the book will do well regardless.

With thanks to Dead Ink Books for the ARC in exchange for an honest review.

[Alessa Mattia · Rating 4 out of 5]

Dark, funny, and immediately captivating. This book had me from page one and never let go.

It follows a college student who desperately needs space for her mental health, for her sanity, following a traumatic event in her life, so she retreats to her cabin in the woods. Isolation sounds healing until she wakes up one morning and finds a dead body outside. From there, the story unravels how the body ended up there, who she was, and what led to her death.

The dual POV is perfectly done. It keeps you engaged, slightly unsettled, and always wanting just one more chapter. The writing style is what really sold me, short, punchy sentences that hit hard. Witty, darkly humorous, and emotionally sharp. It reminded me a lot of *The Wedding People* and that author's signature voice, which I love.

Beneath the mystery, this is a poignant exploration of loneliness, isolation, and mental health. It understands what it feels like to want to disappear without actually wanting to be gone.

Strange, sad, funny, and deeply relatable. For the weird girls.

[Phantas · Rating 4 out of 5]

After a spectacular falling-out with her best friend Savannah chooses to seclude herself at her parents’ lake house for a break when, amidst her loneliness and mental health struggles, she discovers Ava – or her corpse at least – in the woods.

Savannah finally has someone to talk to without judgement, she learns about the last six months of Ava’s life – the hiking trip with her colleagues that went wrong – via her journal and develops a complicated relationship with her new dead friend while also navigating her sexuality and grappling with OCD during her self-proclaimed “corpse hording” situation.

Dual narrated by Savannah and Ava’s notebook, Decomposition Book blends psychological depth with a macabre edge. Dark but often humorous with a smattering of Gen Z/Millennial pop culture references, this book explores love and loss, and the multifaceted way humans experience grief and trauma. Morbidly enjoyable, certainly one for fans of weird fiction!

Thank you to Dead Ink Books & NetGalley for the opportunity to review this ARC. All opinions are my own.

[Carleen Geisler · Rating 5 out of 5]

This book is easily going to be one of my top 2026 releases, and I suspect it will remain near the top of my favorites list for a long time to come. I can think of few books that are hauntingly beautiful in this way—dark, disturbing, maybe borderline grotesque, but more than that: beautifully human in the most raw of ways.

It's a story about a woman recovering in an isolated cabin from her own traumas when she finds a body in the woods. And, instead of reporting it, she befriends it. But, the book isn't really about that. It's about humanity, trauma, and the ways we cope. It's about discovering ourselves, and building boundaries. It's about respect and community, and queer joy.

It's a book that will have you crying real tears onto its pages one minute, and gagging into your lunch the next. It's the perfect balance of beautiful writing, introspection, and strange, quirky plotting.

I'd give it bonus stars if I could.

[Christine Gemberling · Rating 4 out of 5]

If you’re looking for weird girl lit, this is it! I’m new to the genre myself, testing the waters, and I feel like this was the perfect start. A slightly-disturbing setting for a story of mental health struggles and love. Os gives enough details for context of where we’re at [decompositionally speaking], but not so much that it’s a gore-fest. It the right balance for me.
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Being lost in the Adirondack’s is a very real situation that happens, which made this book feel authentic right off the bat. Savannah’s OCD compulsions and intrusive thoughts are well written; mine always get worse when I’m mentally struggling and stressed, like she is. Switching out your real therapist for a dead woman who just listens and can’t talk back is one way to handle it; the arc of this story is satisfying without having to wrap it in a perfect bow.
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Rep: Queer [lesbian], Disability [OCD], lacking racial diversity
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Thank you HarperCollins for this free ARC in exchange for an honest review.

[Megan Magee · Rating 5 out of 5]

Michelle and Savannah are through- so the latter decides to party those feelings off at her secluded lake house, owned by her parents. Not only does she find her second wind there, though- she awakens to find herself nestled beside a dead body. Said body contains a composition notebook full of her experiences trapped in the woods, so obviously our distressed FMC digs through those words rather than report to the authorities. This book is all the things- strange, grotesque, hilarious, winsome, wholesome, sexy, visceral, gritty. So many adjectives, all of them which are so integral to the story. I squealed along with some parts and furrowed my brows until I realized I didn't want wrinkles and forced myself to stop. I related so well to a person who woke up alongside a dead body that I questioned my sanity, more than twice. The references were heavy, and I adored every one. The tidbits with the therapist were so "me" I wrung my hands, but they were also a relief from certain subject matters. I devoured the prose and just recommend this one HIGHLY- the blurbs for Yellowjackets are so apt down to how deeply and darkly funny this was. Thank you to Netgalley and Harlequin Trade Publishing/Hanover Square Press for the digital eARC. All opinions are entirely my own.

[Ashley-Anna · Rating 3 out of 5]

3.5. This was a clever and weird little piece of writing. The MC is flawed, but lovable, and it approaches mental health in a real way that isn’t glamorized. I am left wanting more, however. It is a big buildup that we never know what happens to our MC. I am also a bit annoyed that some of the plot was extremely obvious. There were no twists, but it lets you feel like there will be so it leaves you craving something else. I do love the queer references, the very raw spicy scene, and the moments of humor. It’s extremely fast paced, as well. I just left with too many questions and unsatisfied.

[Tatiana Schlote-Bonne · Rating 5 out of 5]

I loved this book and got to blurb it!! Add to your TBR and preorder now! My blurb:
"I'm obsessed. Sara van Os's narrative voice is so compelling and unique, I was eager to follow it to every deranged, dark place it wanted to take me. Unrelentingly entertaining, Decomposition Book is a wild ride you don't want to miss."

[JXR · Rating 5 out of 5]

emotional and gorgeously dark book with some impeccable vibes and a fantastic main character talking to an apparition of someone whose corpse she found. 5 stars. tysm for the arc.

[Maria · Rating 4 out of 5]

4.25 ⭐️