Kage Kara Mamoru!

Kage Kara Mamoru! is a Japanese light novel that follows the story of Kagemori Mamoru, a seemingly ordinary high-school student with a ninja background. Despite his lackluster appearance and skills, Mamoru is the eldest son of the Kagemori ninja family tasked with protecting their neighbors, the Konnyaku family. The plot revolves around Mamoru swiftly transforming into a ninja to safeguard Yuuna, the eldest daughter of the Konnyaku family, whenever she is in danger. Filled with comedy, romance, martial arts, and shounen elements, this light novel is a blend of humor and action, appealing to fans of harem genres. Noteworthy tags include being adapted to both anime and manga, featuring a male protagonist, and focusing on the intriguing world of ninjas.