"Igano Kabamaru" is a martial arts comedy manga set in modern-day Japan, blending action, humor, and lighthearted drama. The protagonist, Igano Kabamaru, is a young ninja raised in the mountains by his grandfather, a former ninja master. After his grandfather's death, Kabamaru moves to Tokyo to live with his grandfather's old flame, Ran Ogiwara, a wealthy and eccentric woman who runs a private school. Kabamaru's arrival in the city marks the beginning of a series of comedic and action-packed misadventures as he adjusts to urban life while maintaining his ninja skills.

Kabamaru's naivety and rural upbringing often clash with the complexities of city life, leading to humorous situations. Despite his lack of formal education, his physical prowess and ninja training make him a formidable figure. He quickly becomes involved in various conflicts, often defending his new friends and schoolmates from rival gangs, bullies, and other threats. His primary rival is Kirigakure Saizo, a skilled ninja from a rival clan who initially seeks to challenge Kabamaru but eventually becomes a reluctant ally. The dynamic between Kabamaru and Saizo adds a layer of rivalry and camaraderie to the story.

The narrative explores Kabamaru's relationships with those around him, particularly his bond with Ran, who becomes a maternal figure, and his growing friendship with his classmates. The series incorporates elements of traditional ninja lore, such as stealth techniques, combat skills, and the use of unconventional weapons, while maintaining a comedic tone. The plot often revolves around school life, interspersed with larger conflicts involving rival ninja clans and external threats.

Throughout the series, Kabamaru's character evolves as he learns to navigate the challenges of his new environment while staying true to his ninja roots. The manga balances action sequences with lighthearted moments, creating a blend of martial arts and slice-of-life storytelling. The supporting cast, including Ran, Saizo, and various classmates, contributes to the series' comedic and dramatic elements, ensuring a diverse range of interactions and scenarios. The story concludes with Kabamaru solidifying his place in both the ninja world and his new urban life, leaving room for growth and future adventures.