Chibi Maruko chan is the nickname of a sweetly obnoxious 9-year-old girl. She tricks her grandfather, ponders for hours over how to spend her allowance, and hates sitting next to ugly boys. She talks, feels and lives just as real kids do. As the second term commences, Maruko and her classmates return to their small groups. Maruko’s group includes two naughty boys and Maruko is forced to be one of their subordinates. She seems to face a lot of pressure at school.

Our heroine has been kidnapped and her two somewhat ditzy friends decided to save her in a war machine they found in her house. Unfortunately they have little idea of how it works so let the random destruction begin.