The title character, Maruko (born May 8 1965), is a nine-year-old third-grade student raised in a relatively poor family of six. She is lazy, disorganized and usually late for school, in strong contrast with her neat, calm and tidy older sister (sixth-grader) who must share her room with her. Maruko, like many kids, tries to avoid homework and chores, and she takes advantage of her doting grandfather and squabbles with her sister. Nevertheless, she is a well-meaning child who tries to do good.