Ninja Nonsense: The Legend of Shinobu (ニニンがシノブ伝, Ninin ga Shinobuden?) is an anime and manga series by Ryoichi Koga (古賀 亮一, Koga Ryōichi?). The series subtitle is "The Nonsense Kunoichi Fiction". The anime has been licensed and released in North America by The Right Stuf International under the title Ninja Nonsense: The Legend of Shinobu. The translated manga was released by Infinity Studios under the title Ninin Ga Shinobuden.
Ninja Nonsense is an absurdist comedy series which stars Shinobu, a young girl training to become a ninja. However, the series does not focus on ninja training, instead focusing on Shinobu's lifestyle and friends through a series of disjointed comedic plot lines. Towards this purpose, each episode of the anime is split into two separate stories. The series uses character designs that favor a soft and rounded look rather than the slender bishōjo style commonly used in anime or manga series featuring young girls.
The original title of the series is based on a pun. In the Japanese numerical system, ni is two, and shi is four. Ni (2) x ni (2) = shi (4), therefore Ni-ni-n ga Shi-nobuden.