Much to Yuko's chagrin, she experiences yet another sign that she is growing up- her period. Unsure of how to handle the situation, Yuko is thankful for the guidance of Taka-chan, who helps her out and tells her how to deal with the big event. However, with the beginning of this phase in her life, Yuko feels sad and upset. She is really growing up now. Her mom treats the event as a time of celebration, but Yuko feels uncomfortable, especially when her mom tries to tell her dad what happened. Yuko's moods change often, and she gets angry at Hiroshi who at first doesn't understand what is going on. How will Yuko adjust to this new time in her life?