Anina Yatay Salas is 10 years old and is constantly teased by her classmate Ysel, all because of her stupid name. After a fight in the playground, she gets a strange punishment: she gets a sealed envelope, which she is not allowed to open for a week. As a clever girl, she comes up with a plan to open the envelope earlier. At the same time, she gets butterflies in her stomach every time she runs into Natan.