“Why do you kiss clients? It’s like you enjoy being a whore,” sneers Ahd (Eric Bernard) to his colleague (Félix Maritaud). French writer-director Camille Vidal-Naquet takes this question seriously, trying to get inside the head of a young gay hustler working the streets of Strasbourg. The film’s credits refer to the young man as Leo, but he remains unnamed throughout, anonymous, homeless, without a family and in wretched physical health. The camera is agile, mobile, frequently handheld, with crash zooms that feel like double-takes.

There are plenty of uncomfortable, visceral moments to look twice at, including Leo’s flirtations with crack and a violent scene involving two tattooed hipsters and a giant butt plug. When he and a friend rob a rich client’s apartment, the only thing he steals is a stapler to fix his torn jacket. The film offers Leo a way out, but Vidal-Naquet is careful to ensure his choice isn’t a foregone conclusion.

What’s special about the film is how it refuses to moralise about sex work, finding tender moments of intimacy, desire and longing. A beautifully, romantically lit threesome glows amber as Leo lifts a client out of a wheelchair, kissing him passionately on the mouth; he holds another ageing client in his arms until he falls asleep. As Ahd, the object of his unrequited affections, points out, Leo was “made to be loved” and so it’s all the more heartbreaking when he embraces a doctor after an examination, holding her close as though she’s his mother. Maritaud, who was discovered in a bar and debuted in Robin Campillo’s 120 Beats Per Minute, is a revelation as Leo, tough but utterly vulnerable, his eyes alert and adoring.