Moko, who attends a school in Tokyo, spends her days happily with her best friend Hikaru. Their daily routine is to stop by a convenience store on the way home from school to eat snacks and chat. One day, Hikaru has shoplifted, and out of a sense of justice, he scolds Hikaru. She says it was a spur-of-the-moment act, "due to stress from studying for exams," and swears she won't do it again. However, the next day, Hikaru shoplifts again and is caught by the convenience store manager, but he puts the goods in Moko's bag and pins the blame on her.