High school student Kensuke Fuji is utterly obsessed with cats but cannot have one of his own due to severe allergies affecting other family members. Living vicariously through the stray cats in his neighborhood, he spends his free time observing them from a distance, a habit that leads his classmate, Koharu Yamada, to initially mistake him for a peeping tom. Kensuke's devotion is rooted in a childhood incident where a stray calico cat named Tamako guided him home when he was lost, an act he credits with saving his life. When Tamako goes missing, Kensuke's desperate search leads him to a mysterious and eccentric figure known as Neko-ya Jin, a masterful cat whisperer who appears to possess a near-mystical ability to communicate with and command felines. Kensuke witnesses Jin rally the local stray cats to successfully rescue Tamako, revealing a secret feline world he never knew existed. Determined to acquire this knowledge and skill, Kensuke begs to become Jin's disciple and learn the secrets of the Cat Fist Way, a unique path centered on understanding and protecting cats. Jin accepts, beginning Kensuke's formal education in all things cat, which includes not only field observation but also the practical responsibility of caring for a kitten at Jin's home. The story follows Kensuke's journey through the trials and challenges of his unusual apprenticeship, with his classmate Yamada often serving as the grounded, bewildered observer dragged along into this increasingly crazy world of cat-centered martial arts and adventures.