Without meaning any disrespect to the now defunct noughties R&B trio Mis-Teeq, one would be hard pressed to think of many novels that open with an epigraph from their oeuvre. “You know you wanna sing with us (baby). That’s why you know you should be scared of us (baby),” from their 2003 single Scandalous, greets readers of Polly Barton’s debut novel, What Am I, a Deer? It hints at several of the book’s central preoccupations – romance, the disquieting force of desire, and the devotional catharsis of belting out a pop song.

Barton has written two nonfiction books – Fifty Sounds, and Porn: An Oral History – but she is a writer readers are likely to have encountered by accident. Primarily a translator of Japanese fiction, her work includes bringing Asako Yuzuki’s bestseller Butter into English.

What Am I, a Deer?, then, carries a faintly autofictional whiff. Barton’s narrator, an unnamed young woman, has relocated from London to Frankfurt after securing a job translating Japanese for a famous games company, hoping for radical self-reinvention. For years she has harboured the suspicion that she is not a “proper girl” – not quite a right or real person, and certainly not one who moves easily through the world.

The novel opens with a glimpse of the narrator at 12, singing Céline Dion at a school performance. It is a moment of reckless sincerity: half-girl, half-woman, not yet paralysed by the exquisite self-consciousness that will come to define her adulthood. Now in her 20s, she feels she is waiting to arrive in her own life, for some capital-S Something to happen that will finally deliver her into it. Frankfurt, Germany’s aggressively uncool financial capital, seems an ideal setting: a place so nondescript it resembles a blank canvas.

One morning on her commute she forgets her umbrella on the tram. A tall, dark, rakishly handsome stranger retrieves it. The pair barely exchange words, yet this encounter becomes the novel’s gravitational centre. It is a “lightning-strike moment”, and she imagines herself split in two: “She had got on the tram whole and come off divided.”

In the ensuing 200 pages, almost nothing actually happens. The narrator’s fixation on the umbrella man, as she privately christens him, is the engine of the narrative. Barton’s prose is written almost entirely through the narrator’s inner monologue, with virtually no dialogue until the closing pages, and simply charts the feverish interiority of a woman addicted to infatuation. Pining after the umbrella man functions as a kind of analgesic: a simulacrum of meaning that spares her the harder task of living. As she admits, “in many cases of infatuation, what you’re really in love with is the version of that person that lives inside you, which doesn’t have very much to do with that person at all”.

Despite her fixation on the umbrella man, the narrator begins dating a colleague she calls “the stylish man”, though the relationship feels incidental. The games company, dedicated to maximising pleasure and addiction, becomes a sly metaphor for the machinery of obsession. Her emotional life forms another feedback loop of dopamine and dread. “It was impossible to say that she was happy,” she muses, but “she felt at least that she was moving towards a feeling whose relation to happiness was not relevant”.

Karaoke offers salvation. The narrator first developed a taste for it in Japan, and it is this ritual she now practises alone in a soundproofed box, belting out power ballads and reverting to her prelapsarian Céline Dion self. Bursts of capitalised pop lyrics punctuate the prose, unabashedly cliched lines giving voice to feelings the narrator struggles to articulate.

Barton’s prose is offbeat and witty, alive to the excruciating pain of clutching at a romantic fantasy. A good novel tells us about ourselves, scooping out our worst impulses and deepest hopes, and Barton does so with a disarming candour. In its wry observation of millennial ennui, it recalls Vincenzo Latronico’s Perfection, crossed with the emotionally microscopic sensibility of Sally Rooney.

Because the narration rarely strays beyond the narrator’s mind, Barton has ample room to wander down intellectual and philosophical cul-de-sacs, occasionally tipping into overwrought verbosity. She touches on heteropessimism, but the theme never settles. Back in London, the narrator’s partner was a woman, yet she cannot escape the gravitational pull of heterosexuality and the social legitimacy it confers. These insights drift in without fully cohering with the central drama of the umbrella man obsession – Barton’s reflections on gender and social mores sometimes feel like marginalia from a slightly different, more overtly essayistic project. The novel’s title nods to Green Porno and Seduce Me, the oddball web series created by Isabella Rossellini, in which she appears in costumes as various animals to deadpan explanations of their mating rituals. “Are they seducing me?,” Rossellini asks. “What am I, a deer?” The narrator finds strange comfort and humour in the videos, sharing them with her colleagues. In miniature, they capture the novel’s mood: reluctant participation in the strange theatre of desire.

Yet Barton largely pulls off the difficult trick of sustaining a novel in which there is very little plot. It is self-indulgent in the way diaries are: intensely, sometimes clumsily, honest. What emerges is a piercing study of yearning, and of the modern condition of feeling perpetually on the verge of one’s own life. The Céline Dion version of the narrator may ultimately prove irrecoverable. But Barton’s novel suggests that the trick, as with karaoke itself, is to sing anyway.