Hattori, Kanzou

服部貫蔵 (ハットリカンゾウ

Kanzo Hattori, also known as Hattori-kun, is the series' protagonist, a young ninja. He is 11 years old, weighs 40 kg, and stands 140 cm tall. He is the boy who typically challenges Kemumaki when the latter plays pranks.
Hattori's primary weakness is his fear of frogs, which frequently gets him into trouble. He wears blue ninja robes. He constantly explains what a good ninja should do and enjoys interfering in his friends' affairs. His abilities are comparable to those of a master ninja.
He also has a peculiar habit of appending ~degozaru or nin nin to nearly every sentence. His girlfriend appears to be Tsubame.