DEVIL'S VOW: A Dark Irish Mafia Arranged Marriage Romance

by Kaia Voss

He swore an oath to his dying father. He's about to break it for her.

Cian Doyle has ruled South Boston since he was eighteen years old, bound by the vow he made at his father's the family comes first. Always. No wife, no son, no softness until your brothers are settled. For seventeen years, he has kept it.

Then a debt comes due.

The Walsh family owes the Doyles one-point-two million dollars and a reckoning twenty-eight years in the making. There is a way to settle it — a marriage, a Doyle for a Walsh daughter — and Cian does the one thing he swore he never would.

He names himself.

She has been bracing for this since she was eighteen.

Saoirse Walsh runs her dead mother's bakery, keeps her drunk father upright, and protects her little sister from the cost of his mistakes. When the Doyles come to collect, she signs the contract because the alternative is watching everyone she loves lose everything. She walks into St. Augustine's, takes a devil's name, and lets him slide a Claddagh onto her finger with the heart turned out.

What she doesn't tell him — what she's never told anyone — is that she understands every word of the Irish he murmurs against her skin. Her mother taught her the old language when she was a girl. And Saoirse has decided she will not say a word back until the man she married says something worth answering.

He is lethal. He is devout. He is hers — though neither of them will admit it yet.

But there is a rival family circling Doyle territory, an old enemy who remembers a debt of his own, and a threat closing on Saoirse that will force Cian to choose between the vow he made to a dead man and the woman who has become his whole reason for breathing.

When it comes to her, there was never a choice at all.

DEVIL'S VOW is the first book in The Doyles of Southie, a dark Irish mafia romance saga. Expect an arranged marriage, a possessive antihero who is only soft for one woman, a heroine with secrets and steel, a Catholic wedding that means something, and a happily ever after worth the blood it costs. Full-length novel. Standalone with a guaranteed HEA.

Genres: Amazon

325 pages, Kindle Edition

Published May 31, 2026

Reviews

[SsanT62 · Rating 4 out of 5]

Devil’s Vow is the first book in this series featuring brothers in the Irish mafia. Cain and Saoirse enters into marriage but what happens is unexpected.

I enjoyed the lead couple and the author did a great job in developing their characters. The first book in any series lays the groundwork for the following books. There is world building as we get to know the couple, family and associates.

Apparently all the subsequent books are available already so there is no wait if you want the next books. Unfortunately, I will have to wait as I have quite a few more ARCs to finish but they are definitely on my TBR list.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.

[Mafia Wife · Rating 4 out of 5]

She has been holding her family together since she was 18, running the family bakery, keeping everything together, but she knows she’s on borrowed time. When they come for the dead, she knows she doesn’t have a choice, but to enter the marriage contract. He dedicated his life too, putting family first. When her family debt comes due, he does something he never thought he , he marries her. This one is an arranged, marriage family with the drama you expect, and the hard one happily ever after. They have every reason not to work, but the possessive driven alpha in him is drawn to the spicy girl with the spine of steel, who would do anything to protect her family.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.

[K T · Rating 5 out of 5]

Cian & Saoirse's story is unique!! In a fun & interesting way. The book is fast paced. I like arranged marriage stories & enjoyed this one and how it played out.

There are some interesting, unexpected plot twists, which was nice!

This is Book 1 in The Doyles of Southie series. I look forward to the rest of the series!!

The book is told in dual 1st person POV

Spice level: 3/5

*Irish Mafia romance
*arranged marriage
*forced proximity
*morally grey characters
*marriage of convenience
*possessive/protective Alpha hero MMC
*romantic suspense

Thank you to the author (Kaia Voss) & Booksprout for the ARC. All opinions are my own.

[Nikita Lavelle · Rating 5 out of 5]

⭐️⭐️⭐️⭐️⭐️

Just finished Devil’s Vow by Kaia Voss, and I absolutely loved this story!

Give me an Irish mafia romance and an arranged marriage, and I’m there! 😍

I really loved Cian and Saoirse and their story. This was one of those books where I kept finding myself wanting to go back to it because I just wanted to keep reading and see what happened next.

I’ll definitely be continuing with the rest of the series because I need to know where the story goes from here! I also want to see the brother’s stories.

And honestly, if these books were available in traditional paperback, I would be buying them too. That’s how much I enjoyed this one!

[Holly Couch · Rating 4 out of 5]

Devil's Vow is the first book in a series featuring brothers in Irish Mafia. Cain and Saoirse enters into a contracted marriage and what happens next unexpectedly.

I enjoyed the first book of this series I can't wait to read the next book . The author did a great job with the characters.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.

[brenda hurley · Rating 5 out of 5]

This was a great way to start this series. I thought this book was intense that had me on the edge of my seat while turning the pages. It was well written. Can’t wait to read the next book in the series.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.