"Itoshi no Nekomimi Ri-man" centers around the life of Riku, a young man who unexpectedly inherits a cat-eared maid café from his late grandmother. The café, named "Nekomimi House," is a quaint establishment known for its unique theme where the staff dress as cat-eared maids and butlers. Riku, initially reluctant to take on the responsibility, finds himself drawn into the quirky world of the café and its eccentric employees.

The narrative explores Riku's journey as he navigates the challenges of managing the café while balancing his personal life. The staff includes a diverse cast of characters, each with their own distinct personalities and backstories. Among them is Miu, a cheerful and energetic maid who becomes Riku's closest confidante, and Haruto, a stoic butler with a mysterious past. The interactions between Riku and the staff form the core of the story, highlighting themes of friendship, responsibility, and self-discovery.

As Riku becomes more involved in the café's operations, he encounters various obstacles, from financial difficulties to rival businesses attempting to undermine Nekomimi House. The series delves into the daily struggles and triumphs of running a small business, emphasizing the importance of teamwork and perseverance. Alongside the professional challenges, Riku also grapples with his own insecurities and aspirations, gradually growing into a more confident and capable individual.

The manga blends slice-of-life elements with lighthearted comedy and occasional moments of drama. The cat-ear motif serves as a recurring symbol of the café's charm and the unique bond shared by its staff and patrons. Through its engaging narrative and well-developed characters, "Itoshi no Nekomimi Ri-man" offers a heartwarming portrayal of community, personal growth, and the enduring appeal of a beloved neighborhood café.