Once a Villain

Monsters #3

by Vanessa Len

The final book in the lauded Only a Monster trilogy is here—where the unstoppable love and high stakes of Divine Rivals meets the propulsive thrills of This Savage Song in a last-ditch, breathless race against time.

Joan has failed to stop Eleanor.

Now Eleanor rules over a cruel new timeline where monsters live openly among humans, preying on them and subjugating them.

Nick—once a hero to humans, and Joan’s first love—is tormented by the choice he made to save her over the timeline itself. And Aaron—the ruthless heir to a powerful monster family—now finds himself in a world where monsters have power beyond imagining while his feelings for Joan grow.

Wrenched between love and rivalry, the three of them must negotiate their fractured pasts to survive the new world and restore what was lost. Because only they remember that there was once a better timeline.

But how will they defeat a whole world of monsters with control over time itself?

Genres: Fantasy, Young Adult, Romance, Time Travel, Young Adult Fantasy, Romantasy, Paranormal

416 pages, Hardcover

First published August 19, 2025

About the author

Vanessa Len is an internationally bestselling Australian author and educational editor. Her first novel, Only a Monster, won the 2022 Aurealis Award for Best Young Adult Novel, and has been translated into nine languages. The sequel, Never a Hero, is out now.

Reviews

[siu]

just might riot if team aaron is not endgame <3

[TheRosePages]

No thoughts but Aaron Aaron Aaron

[.*zayda*. warner-kavanagh-cyrus-cardan-hudson-wes's version]

2024...I have to wait until 2024... Bruh. Waiting for books to come out is the worst form of torture known to man I freaking swear.

[Wicked Fox ✨️]

BEGGING for Aaron to be endgame

Vanessa plssss 🙏

Edit: WE HAVE A COVER 😭

[Kaitlynne · Rating 5 out of 5]

BEFORE READING IT:
We're manifesting for even more Aaron Aaron Aaron...

AFTER:
I need some time to process everything. I'm still feeling big emotions. I went over 12 hours between being at 98% and finishing it. now I need at least that long before I can try writing a review 😂

Mini review after having time to process:

I survived. Just barely. This book took me on a roller coaster of emotions. There was a plot twist that I didn't see coming, but I'm not necessarily mad about it. I love the character development that we got. I don't want to say too much because it's so far out and I don't want to spoil anything. A full review will be coming closer to its actual publication date.

Thank you Harper Collins for this ARC, you made my week so much better. All thoughts and opinions expressed are entirely my own.

[☂️]

all I want is for this book to be full of aaron oliver

[Ashley Catelyn · Rating 2 out of 5]

Wtf was that ending😭

Quotes:

"Aaron's gaze flicked to Joan as if by instinct."

"We don't touch what isn't ours." Aaron sounded ice cold—exactly like his counterpart."

Pre review (30/8/23):
I need to read this book immediately and if Aaron isn't endgame I will sue.

[ScavengedReads · Rating 5 out of 5]

GIVE THE PEOPLE MORE AARON

Send Nick off on his villian era. We don't need him, he's over stayed his welcome.

[Shreya ◠◡◠]

not 2024- I- *screams into void*

[Isabelle (the Book Dutchesses) · Rating 4 out of 5]

Can't wait for this one! The title better be Always A Villain!

[braidee · Rating 5 out of 5]

gonna cry aaron better be the star of this book

[kaylee · Rating 3 out of 5]

vanessa len if i was your editor nick ward would have been deleted two books ago. everything felt rushed and everyone felt sooo out of character!!! IN ACTUAL DISBELIEF.

[Ayala]

rooting for aaron and joan endgame 🙏

[✨Chigozie~Cozy✨ · Rating 5 out of 5]

I get that it's Nick x Joan in the "True Timeline", but we all know that ✨Aaron Oliver✨ MUST be endgame. We will not settle for anything less.


UPDATE JULY 2024:
For anyone who’s interested, I sent an email to Vanessa asking for some kind of update and was told we can expect the final instalment around this time next year! 🙌🏼

[Cindy ✩☽♔ · Rating 4 out of 5]

Not the ending I expected, but the ending our characters undoubtedly deserved.

After waiting two years, I can happily say this book was worth the wait. It took me a little more time to get reacclimated to the world and the plot due to the longer time between books. That being said, once I was able to dive back in, everything progressed pretty quickly.

I genuinely enjoyed being back with our rag-tag team of misfit heroes—even Nick, whom I did not like much in the previous installment.

The conclusion to the love triangle is the best I could have hoped for. Thank you to the author for going a route I did not think she would go.

All the storylines wrapped up nicely, albeit a bit conveniently, but sometimes it's nice to see our protagonists get their well-earned happy ending.

Thank you to NetGalley and Avon/Harper Voyager for providing me with an advanced reader copy. All opinions are my own.

[Lyrette · Rating 5 out of 5]

oh my god im gonn a cry

[countess_matcha]

Why do I get the feelings this isn't actually coming out in 2024?💀

[Masha (onceandfuturebooknerd)]

I want to point out that the only option there is is polyamory 😌 There are no separate teams, just team "everyone happy and in love" and there is that. 🤝🏻🩷

[S A · Rating 1 out of 5]

I was so excited for this book to come out, and had even prepared by re-reading the last two. So it genuinely pains me to write that I could not be more disappointed. In what world would Nick, Joan and Aaron be in a throuple? Genuinely so stupid.

[mishaal !]

Ignore me whilst I stalk my dear Vanessa Len. 💃

[Ezgi T]

10/02/24: for the second book, i tried to manifest more of aaron and less of nick. it didn't work out.
this is another attempt.

manifesting aaron endgame. and nick to erase himself from the story, thank you.

also, when are we getting a title, a release date, anything? i wasn't able to find any information online whatsoever.

[Jessica · Rating 4 out of 5]

First of all, a huge thank you to HarperCollins Children's Books and NetGalley for providing me with an ARC!

You have no idea how hyped I was for the finale of the Monsters trilogy. After the ending of book two, I had to know how the story around Joan and co. would end – and of course, whether she'd ultimately choose Aaron or Nick. I’m so grateful I had the chance to read this early, and I can assure you: this book delivers a thrilling finale full of unexpected twists!

The story picks up right after the dramatic ending of Never a Hero, so I definitely recommend rereading the last few chapters of book two to refresh your memory. Just like the previous books, I really enjoyed this one (and that’s coming from someone who normally isn’t a fan of time travel – or am I now? 🤭)

The worldbuilding, especially the “monsters” concept, was absolutely fantastic. I also loved how the relationships were written: romance, friendship, family bonds and even the tensions between the different monster families. Everything felt so well developed. I was emotionally all in and I truly couldn't put the series down.

Once a Villain once again brings high-stakes action, suspenseful twists you’ll want to unravel, and a whole lot of romance and emotional chaos. I started to guess the outcome of the love story at some point – and honestly, I was rooting for it to go that way 🤭

But I also do have a few critiques: Some decisions didn't fully make sense to me, and there were a few plot holes or missing explanations that genuinely bothered me. The ending also felt a bit too easy and rushed. As a reader, I got the impression that certain plot threads weren’t fully thought through, because some things felt like they were quickly wrapped up or even completely “forgotten” 🥲

Still, since I truly enjoyed this book – and the entire trilogy – I won’t go into more detail (also to avoid spoilers ahead of release). Despite a few minor flaws that kept me from giving it a full five stars, I wholeheartedly recommend this series to anyone who loves time travel stories and romantasy! ❤️

P.S: Vanessa Len is now officially on my immediately-to-buy list 😍 I’d love to see a spin-off set in this world – maybe it could even address some of the unresolved questions? 👀

[Reece]

I haven't finished the second book yet, but I already don't want the series to end. It's one of the best YA series I've come across, and constantly surprises me with its time travelling magic system: innovative, imaginatively fun, yet comes at such a terrible cost.

[millena &#x1fa90; · Rating 3 out of 5]

well, that was a surprise……. rtc closer to release date

thanks edelweiss & harpercollins for the arc 🖤

[Krissi · Rating 2 out of 5]

Thank you to Netgalley, the publisher, and the author for providing a free e-arc in exchange for an honest review.

Well, this series wasn't particularly mind-blowing to begin with, but this last book was just...feel mean for saying it...not good! The mature themes that are mixed in with what's labeled as a young adult book was off-putting, as well as the ridiculous, and I mean ridiculous love triangle that unfolds before us was just laughable. It took me back to the Twilight days of people wanting threesomes between Edward, Bella, and Jacob...just no... The concept of resurrection throughout the book was also poorly done and didn't really contribute anything of substance to the story other than knowing if someone dies, they're just going to come right back. This author's work is just not for me, but if the series sounds interesting to you, give it a try as you may like it.

[Azul Juarez · Rating 1 out of 5]

I waited two years for this book, very excited, and it turned out to be a disappointment. Vanessa touched on very ambitious themes and developed them poorly. That trio was VERY forced, and Joan's failure to develop and learn to handle her powers and her monster side made it much worse. I feel like Vanessa wanted to please both ships and only ruined it for both of them.
Joan, Aaron, and Nick deserved better than this.

thank you to edelweiss and harpercollins for the arc

[Diksha Rawat]

please dear author give me this book 😭😭😭😭

*uncontrollable chanting of Aaron's name*

edit- GUYS WE HAVE A GORGEOUS COVER!!!!

[Val · Rating 2 out of 5]

too ambitious for its own good. the mature themes sink under the weight of YA quicksand.

thank you to edelweiss and harpercollins for the arc 🌷

[Minna · Rating 5 out of 5]

Release date: August 19th!!!

Ohhh my god, where do I even begin? The final book in the Monster series is HERE and what a RIDE it was. I have been waiting for this book since last year, and it did not disappoint at all. I binged this under 24 hours, and was that the smartest thing to do? NOT SURE, but I literally couldn't put this book down. It had me screaming, nauseous, and giggling!!! I felt like I was getting whiplash the entire time, because so much was going on (in the best way).

I have to say out of the three books, this is definitely the darkest in the series, and oh man. I cannot say too much, but the way that I was physically ILL reading certain parts of this book (sort of in dystopian horror kind of way?), and I just want to say, thank you Vanessa Len for adding in the perfect amount of comedic relief throughout this book. Every time I'd start feeling nauseous or unwell, Aaron and Ruth would start arguing about clothes and fashion, and it just never failed to make me laugh. It's the end of the world, but Aaron Oliver still wants to make sure he looks good. 😎 Priorities!!!

And I really should've known from the dedication that we would see certain scenes in here, and oh my god did it break my freaking heart. I teared up multiple times for Joan and Aaron. I've discovered that stories such as this one with multiple timelines and time travel freaking kill me. To remember someone, and have them forget you. To know someone so deeply, and have them look at you like a stranger. Stab me straight through the heart. The writing is absolutely phenomenal, and the author does just an amazing job making you feel so devastated for this characters.

Now you're wondering, okay but what about the love triangle?! Team Nick?! Team Aaron???! I've said it before, and I'll say it again. This is a love triangle done RIGHT. I was Team Aaron for book one, and then it became all a haze from then on, because NICK AND AARON ARE BOTH SO GOOD?? And honestly I couldn't have asked for a better ending for the three of them. This was everything I wanted, truly. My only complaint (is this even a complaint) is that I wanted maybe like 50 more pages. A longer epilogue would have been nice, because now I just feel a little dead inside 😭

The acknowledgements said goodbye to Nick, Joan, and Aaron (for now), and I am on my knees begging. Desperate for any scraps the author might give us, because I would read any kind of spin-off, novella that the author wanted to do in this world. ORRRR, A BOOK FOR JAMIE AND TOM?

Anyways, all I am trying to say is I love the series so much, what a great conclusion to this story. I am devastated that it is over, and I will support this author with any new projects in this Monsters world, or completely new. Thank you so much for writing a book that made me feel seen, younger me would've cried to see a half asian gal being the protagonist of a story.

(Thank you Vanessa Len for the gifted copy, and Harper Collins/ Epic Reads for the finished copy! <3)

[norah · Rating 2 out of 5]

thanks to NetGalley for the eARC

⭐️=2.25 | 😘=3 | 🤬=4 | ⚔️=3.75 | 15/16ish+

summary: Only a Monster book 3 (finale to the trilogy)

thoughts: 🚨🚨🚨🚨🚨spoiler-ridden review!! beware!! 🚨🚨🚨🚨🚨

- WHAT IS THE SIGNIFICANCE OF THE PIN AARON GIVES HER IN BOOK ONE WHAT IS THE SIGNIFICANCE U NEVER EXPLAIN IT WHY IS IT SO MEANINGFUL TO AARON IN EVERY TIMELINE WHY I NEED TO KNOW

- this was plotted out so haphazardly?? literally on the last page there’s this joking line of dialogue like “hey you still owe the Lius two favors” and everyone is like “lol!” but this is NOT lol this is a serious unresolved plot thread from book one!! like did you know what you were going to do with that when you wrote it, Vanessa?? why did this go ignored??

- also the fact everyone has been resurrected via different timelines at least once, sometimes way more times than that, made the emotional stakes of this book, like, zero? because now I know that none of the characters I am supposed to care about will die, and if they do “die” they can easily be alive again. I realized this partway through the book and then the rest of it was, like… consequently dull.

- I understand that a throuple is thematically necessary to resolve everything—human vs monster, where do you find a place to belong when you’re stuck between two worlds et cetera—so having a throuple with a human, a monster, and a human/monster (rather than traditionally resolving a love triangle) answers that question, and that’s fine, and that could have worked, but I truly canNOT believe that the Aaron and Nick of this timeline would be able to fix their issues (like Aaron being responsible for the thousands of years of human death and that being specifically against everything Nick believes in) enough to enter a romantic and sexual relationship between the two of them, let alone alongside Joan?? like these are TEENAGERS they’re not going to get over their trauma (that distinctly pits them morally against one another) over the course of the one book??? I get the underlying intent but it is impossible to follow through in a believable manner under the circumstances with these guys specifically. I don’t believe it.

- I hate the circumstances under which Joan and Aaron have sex. Joan was not in an emotionally safe place, and it was such an irresponsible circumstance and it gave me the ick

- the sad thing is that the first book of this series was SO perfect. and this is so not and was clearly unplanned bc of all the unfinished threads—both literal plot things and character development. rest in peace Once a Villain, you would have loved being a strong ending to this trilogy!! tbh I feel like this should have been four books, or at least extended so that we got flashbacks to alternate timeline memories between Eleanor and Joan bc then we would care more about them and the stakes there and therefore things were not set up deliberately and it’s just maddening!!