Marion is a 14-year-old girl who is on holiday with her family by the sea in Normandy. But she soon comes into conflict with her mother and siblings. There she also meets a man named Marc, to whom she feels attracted, who sees her and desires her. Back in Paris, she visits him again. For the first time in her life, she will make love to him.

Nicolas, an aimless adolescent who hasn't yet found his way in life leaves his grandparent's home, hitchhikes to a small town, and befriends, Charly an outspoken and slightly older prostitute, a red-headed beauty who appears to ply her trade in the same no-nonsense way she clears the breakfast dishes. She seems to find something endearing about Nicolas' mussed hair and dopey face, so she puts him up in the teeny trailer home that she maintains with such hilarious fussiness. As their unusual domestic arrangement evolves, each stumbles vulnerably into new emotional territory.

Demi-Tarif follows the low-key adventures of three young siblings, Romeo, Launa, and the youngest - Leo, left on their own in a rundown Paris apartment. One of them narrates, wistfully explaining how their mother abandoned them and calls them once in a while to see how they are doing or tell them she loves them. The three kids do as they please, roaming the streets, running out of restaurants without paying for food, and shoplifting from the local grocery store. They eat whatever and whenever they want, gorging themselves on sweets. They beg for change on the Metro and show up late for school in tattered, dirty clothes. All the while, they try to keep the fact that they are alone a secret from the world of adults.