Valentine is a secondary-school student like many others. Her daily life is filled with all the upheavals and self-questioning of adolescence. Self-conscious, she tries to assert herself within a group in which she is "the shy one". She spends most of her time with her girlfriends, at school or at parties on the weekend. She also tries desperately to get the attention of Felix, the boy she's in love with – and who has no idea she exists. To make things worse, he's in the "rival" class to her own... Little by little, this young woman learns to express herself and find her place in the cruel and treacherous world of adolescence, from MP3 players and Japanese mangas, to her first parties and her first whiskey and Coke.

Going into their last year of middle school, Valentine and her friends are at that defining time of their lives when new experiences are coming thick and fast. They've got their finals just around the corner, but that doesn't stop them from bunking classes and flirting with guys (even if, in Valentine's case, they're not the guys she actually wants to flirt with... the gorgeous Felix is as aloof as ever). Valentine struggles to find her feet in this emotional whirlwind.

In the third volume of the series, Valentine enters into her first year of high school. Bad news! The group of four girls is split up into different classes. At first it looks like Valentine's the unlucky one—the kids in her class are decidedly uncool. But once she gets to know them a little better, she starts to see that maybe she was wrong to judge so quickly.

Valentine is in her second year of high school and once more in a class where she doesn’t know anyone. But that won’t stop her from living her the manga club, her hip-hop group, and her lunch breaks give her a chance to catch up with her friends. That is, when Yamina isn’t hanging out with her new boyfriend! Valentine will soon be 17 years old, but she still blushes as much as ever when she sees her crushes coming her way. If only she could think of something to say to Félix, beyond asking him if he’d like a glass of water…