The time is the near future. Cockroaches and other household pests have become immune to all forms of insecticides. In response to this crisis, a Japanese company has created small, doll-like, insect exterminating robots called Hoi Hoi-san. A competing company has also released their own version, Combat-san. Because of their adorable appearance, these little robots have become somewhat of a phenomenon and have gained many fans. Late at night, in the home of one such fan, Hoi Hoi-san and Combat-san search for insects to exterminate... but Combat-san is not above trying to exterminate Hoi Hoi-san while she's at it.

Third-grader Himeno moves to a huge mansion in the country. However, she soon finds out it's a ninja house! The ninjas Akamaki, Aomaki, and Kiiromaki mistake Himeno for a princess and begin solving problems for her with their own unique skills. But that is not the full extent of their powers! When Aomaki and Kiiromaki combine, they form Midorimaki. Similarly, when Akamaki and Aomaki combine, they form Murasakimaki; and when Akamaki and Kiiromaki combine, they form Daidaimaki. Life with these colorful ninjas has only begun when they discover a large tornado heading for the mansion. What will happen to Himeno's family? Can the colorful ninjas protect Himeno?

The story centers on an introverted high school student named Eiji Hoshimiya with a huge secret—he wished for the destruction of the world when he was younger. Fairies give certain people special powers called Orders, and what Order Users can do with their power depends on their wishes. Ten years after the Great Destruction, Eiji struggles to come to terms with his immense power.

A comedy about a family of old-fashioned samurai living in modern-day Tokyo whose young son has to head out for an important date.