Convenience Store Woman by Sayaka Murata just might be the most surprising and unexpected love story you'll ever read. Intriguingly, there's no relationship in the novel between two characters in any conventional sense of a loving narrative; there are no marriages or divorces; there's no mother/father or son/daughter tales of growth and parental/child love; and nobody dies.

Keiko Furukura has never really fit in. At school and university, people find her odd due to her penchant for bizarre actions – at the former, she bashes a boy over the head with a shovel to stop him from fighting. At one point, she even asks her mother if she can cook a dead budgie she has found in the park. Her family, understandably, worries she'll never be normal.

To appease them, 18-year-old Keiko takes a job at a convenience store, Hiiromachi Station Smile Mart. Here, she finds peace and purpose in the daily tasks of shelf restocking, product promotions and routine interactions with customers and staff. She comes to understand that she's happiest in the mundane role at which she excels, with its morning chorus of Irasshaimase!, meaning "Welcome!"

Murata writes: "When I can't sleep, I think about the transparent glass box that is still stirring with life, even in the darkness of the night. That pristine aquarium is still operating like clockwork… When morning comes, once again I'm a convenience store worker, a cog in society. This is the only way I can be a normal person." Keiko's response is sensitive to the store's aura, as she becomes a "convenience store animal" who can "hear the store's voice telling me what it wanted, how it wanted to be."

Therein lies the problem. Keiko is now 35 and, in the constraints of her social circle, it just won't do for an unmarried, childless woman to spend her life stacking shelves and reordering green tea, a job ordinarily performed by part-time students. Friends and family pressure her to seek therapy, find a new job or, best of all, a husband.

At which point in lollops the character Shiraha, an unusually lanky, lazy and opinionated sort who thinks humanity hasn't evolved from the Stone Age and whose truculence soon gets him sacked, only for Keiko to take pity on him.

In the standard narrative, our two protagonists would overcome their idiosyncracies or be drawn to them, and fall in love. But that has nothing to do with this story. With echoes of Kaori Ekuni's Twinkle Twinkle, Keiko tells the misfit Shiraha he can move in with her, where she will provide and keep him "hidden from society". In return, her family and friends will consider her normal for having a man in the house. "If a man and a woman are alone in an apartment together," she tells him, "people's imaginations run wild and they're satisfied, regardless of the reality." Shiraha concurs, telling Keiko that on a functional level, "Everyone will assume you're a sexually active, respectable human being. That's the image of you that pleases them most. Isn't it wonderful?"

A bestseller in Japan and the winner of the prestigious Akutagawa Prize, Convenience Store Woman, Murata's eighth novel in Japanese, marks her English-language debut and she's been hailed as the most exciting voice of her generation. Remarkably, the author is also a convenience store worker and wrote her novella from 2am until 8am each night, after which she would go to work at the convenience store, which she has credited as being an antidote to her former shyness.

Blindingly good and strangely comforting from start to finish, the novella is clever, terse, quirky, poignant, poetic and funny, Keiko's world of total contentment – with nary a tweet, Instagram or social media platform in sight – and its luminous linearity stays with you long after reading it. And zen some.

Keiko couldn't be any more unconventional when it comes to the expectations of the contemporary Japanese female. Convenience Store Woman is a mini-masterpiece of intimacy, a revelation at hand. Read and relish the love story of the century – a compelling marriage of convenience.