Ahead of the publication of her debut novel, Tony Hogan Bought Me An Ice Cream Float Before He Stole My Ma, Aberdeen-born Kerry Hudson told an interviewer she wanted to write about "what it's like for a woman growing up in working-class Britain".

To some extent its follow-up applies the same intention to a man - 20-something Dave, who was raised on a south London council estate, works security at an upmarket London store and jogs to escape his problems and cleanse his soul. Of what, we learn only late on in this bittersweet love story.

Dave's life is one fenced in by booze, fags, nights out with the lads and nights in with the telly. Money's tight, opportunities are few and even his dreams have a price tag - he's saving for a plane ticket to one of the destinations in the Lonely Planet travel guides that sit by his bed.

But on to Dave's story Hudson bolts another by giving equal star billing to Alena, a pretty Russian girl whose recent past is slowly revealed to the reader and (slower still) to Dave. They meet when he collars her during a superbly inept shoplifting spree and he falls for her gamine charms. Like him, she has secrets and a past she's seeking to escape, or at least stay one step ahead of. And so these damaged people come together to share a refuge - or, in this case, a one-bedroom flat above a Hackney kebab shop.

There are walk-on roles for a host of others characters who are introduced in flashback - Dave's mum, Pat, who will fall ill with cancer; his best friend, Deano; local girl Shelley, who's "perfectly made up and entirely f***** up" and who Dave marries by mistake; and Andriy and Fedir, a father and son pimp/gangster/sexual predator team who have a streak of nasty through them the size of the Russian steppe.

It's the storyline involving Fedir and Andriy which is the strongest and it's only when Hudson lets it begin to unfold about a quarter of the way in that the novel really picks up speed. Hudson tackles the scourge of sex trafficking head-on through a graphic description of Alena's treatment at their hands. She's first duped and then, when she arrives in London looking for a better life, snared, like thousands before her. She is abused, beaten and imprisoned then put to work luring other wide-eyed arrivals into the same world of sex slavery. She frees herself with a false promise of love to the violent Fedir. He falls for it, and she heads for a women's refuge. A few days later, she meets Dave.

Hudson's rendering of Dave is less successful. To put it plainly, he's a little dreary. He goes to and from work, worries about his life and day-dreams about Alena. Meanwhile the object of his affections moons around his flat, looks in vain for a job and, when he comes home tired and sweaty to kick off his shoes and collapse on the sofa, shows him just enough flesh and lavishes on him just enough attention to make him extend his offer of a couple of nights on the sofa to a week/a month/as long as she likes. That's the game she think she's playing anyway. The irony is, he's delighted to have her there and has no intention of chucking her out. And he is, as he often stresses, expecting nothing in return.

By nothing he means sex, of course. It's a currency Alena understands all too well, though, so when Fedir reappears on the scene she knows how she's going to have to pay up. From there, the narrative picks up again and a final passage set on a journey across Russia - a journey Hudson herself made while researching Thirst - is one of the novel's strongest as the two star-cross'd protagonists finally find the courage to put the "love conquers all" mantra to the test.

Kerry Hudson appears at the Edinburgh International Book Festival on August 25.