10-year old Ken (Ken'ichi) Mitsoba is an average kid who goes to elementary school, and struggles with his studies. Meanwhile from ninja land aka Land of the Ninjas, a little ninja named Kanzo Hattori comes, and befriends Ken'ichi. Hattori is now a part of the mitsoba family along with his brother Shinzou, and his ninja dog, Shishi-Maru. Hattori helps Ken'ichi with his problems, and constantly keeps an eye on him, as a good friend.

Each chapter follows Fukuzou Moguro, a traveling salesman, and his current customer. Moguro deals in things that give his customers their heart's desire, and once his deals are made and their unhealthy desires are satisfied, Moguro's customers are often left with terrible repercussions, especially if they break the rules of his deals...