Kostya is left home alone for a whole week. Instead of exercising, he thinks about only one thing: how to lose his virginity as quickly as possible so he can truly become an adult. Kostya asks his classmate Katya out on a date, but backs out at the last minute. Trying to rectify the situation, he agrees to a party at his house.

Katya comes to Kostya's party and quickly finds herself the center of attention. After an awkward moment, his friends betray him, and Katya leaves. Nika helps him come to his senses. The girl dreams of his attention, but Kostya sees her as merely an assistant in his struggle for his friend's affections.

Kostya invites Katya on a date to the equestrian club. During their ride, the boy indulges his lover's every whim. When he tries to kiss Katya, she refuses, citing his complete inexperience with girls. Kostya begins to imagine that everyone now knows his secret.

On the advice of his friends, Kostya goes to a massage parlor to find help with his problem. He meets Masha there, but at the most crucial moment, he runs away again. Having completely failed his workout, he pours out his heart to Nika, and unexpectedly, she makes him a tempting offer.

Nika learns about Kostya's visit to the massage parlor and leaves. Some time later, Lom visits Kostya, who is angry that he was the last one to know about it. Kostya confesses that nothing actually happened at the parlor. Now he desperately wants Nika back.

Kostya can't understand what kind of relationship he has with Nika. In a fit of rage, Nika suggests they break up. All the guys come to Lom's birthday party. Katya actively tries to seduce Kostya, which offends Nika. Nika leaves the party, and Kostya commits an unpleasant act.

To make peace with Katya, Kostya goes to the pool. He's afraid to tell the truth about the kiss, but decides to do so anyway. Upset, Nika throws Kostya into the pool and leaves. Lom arrives to rescue him, but they also quarrel after a while. To get his life back on track, Kostya decides to take an important step.

Nika and Kostya are sitting in the kitchen. The guy tries to escape again, but she stops him, and they start a conversation that gradually turns to that very first time. Only the sex turned out to be completely different from what they imagined.