Etsuko is a Grade Two student and cheerful, but sensitive girl. When she arrives at school, George is mean as usual. Etsuko gets frustrated from morning. When her friend, Sally, gets hurt during music class, Etsuko thinks George has hurt Sally on purpose. Etsuko loses her temper and gets into a fight with George. After the fight, she feels terrible about being messy and scolded by the principal. On her way home, a mysterious cat appears in front of Etsuko and gives her a wooden box and an important message: be true to her heart and always remember that she is never alone. What does the message mean and what is the box for?