A novel about a serial killer and a children’s book about a dog are the books of 2024, according to Waterstones booksellers.

Butter by Asako Yuzuki, translated from Japanese by Polly Barton, has been voted book of the year, while I am Rebel by Ross Montgomery has been named children’s book of the year.

Inspired by the real-life case of the “konkatsu killer” who poisoned three of her lovers, Butter follows a journalist who becomes increasingly obsessed with a convicted killer who seduced her victims with her home-cooked food.

“This is a thought-provoking and surprisingly feelgood take on friendship, transgressive pleasures, and society’s impossibly contradictory expectations of women,” wrote Laura Wilson in the Guardian.

Yuzuki said that she was “really happy” about Butter being named book of the year. “I feel honoured. It’s the best Christmas present I could have hoped for.” She hopes that the book inspires readers to question social norms.

The novel “is the ultimate word of mouth sensation, a deliciously rich treat of a novel which quickly established itself as the most talked-about book of the year”, said Bea Carvalho, head of books at Waterstones.

“Weaving tense mystery with blistering social commentary and skewering the media’s obsession with true crime, fans of fiction of all kinds will devour Butter,” she added. “As well as its brilliant storytelling and elegant translation, Butter is a true publishing masterclass which raises the bar for book design.”

Waterstones booksellers were asked to nominate a book that they particularly enjoyed recommending to readers over the past year. This led to a shortlist of 15, from which a panel selected the two winners.

I Am Rebel is about the bond between a dog and his owner, Tom. “At a time when children’s literacy and reading for pleasure should be at the top of everyone’s agenda, I Am Rebel stands out as the perfect book to press into the hands of children and the adults who care for them,” said Carvalho.

“It is a book to remind adults of the joy and wonder to be found in children’s books, and to help young readers discover a love of reading,” she added. “Firmly rooted in the traditions of the classics like all the best comfort reads, yet wholeheartedly, originally itself, I Am Rebel is above all a brilliantly fun gripping adventure which showcases the very best of children’s storytelling.”

Montgomery said that he was “blown away” by the news that I Am Rebel had been named children’s book of the year. “Whenever you sit down to write a new book, you always have high hopes for it, but I don’t think I could have predicted this in my wildest dreams.”

“I’ve been a kids’ writer for 11 years now, and this is something like my 30th book,” he said. “To have this kind of accolade so far into my career is an incredibly special thing, and I’m definitely more appreciative of it as a result.”

“I want kids to put the book down when they’re finished with wet eyes and a heart as big as their chest, filled with joy and wonder at the world,” he added. “I definitely didn’t want to devastate them, so no dogs die in this … and I made sure to put a disclaimer on the back saying just that.”

The two winners will receive the “full and committed backing of Waterstones shops and booksellers across the UK”, as well as support online.

Alongside Butter and I Am Rebel, other titles shortlisted this year were Intermezzo by Sally Rooney, Long Island by Colm Tóibín, Blue Sisters by Coco Mellors, Glorious Exploits by Ferdia Lennon, The Garden Against Time by Olivia Laing, James by Percival Everett, Raising Hare by Chloe Dalton, The Reappearance of Rachel Price by Holly Jackson, Easy Wins by Anna Jones, Eighteen by Alice Loxton, The Siege by Ben Macintyre, Cloudspotting for Beginners by Gavin Pretor-Pinney and William Grill and Shakespeare’s First Folio: All the Plays – A Children’s Edition, illustrated by Emily Sutton.

Last year’s book of the year was Impossible Creatures by Katherine Rundell, while the novel of the year was In Memoriam by Alice Winn, and the gift of the year was Murdle by GT Karber. Sales of the winners “soared and dominated the charts after announcement”, according to Waterstones, with Murdle becoming the overall Christmas No 1.

Other previous books of the year include Hamnet by Maggie O’Farrell, The Boy, the Mole, the Fox and the Horse by Charlie Mackesy, Normal People by Sally Rooney, The Essex Serpent by Sarah Perry, and The Miniaturist by Jessie Burton.