"Shiba-wanko no Wa no Kokoro" centers around the daily life of a Shiba Inu dog named Wa, who lives with a young woman referred to as "Owner." The series is a slice-of-life comedy that explores the humorous and endearing interactions between Wa and Owner, as well as Wa's observations of human behavior and the world around her. Wa is portrayed as a highly intelligent and self-aware dog, often providing witty and sarcastic commentary on her Owner's habits and the peculiarities of human life. Despite her sharp observations, Wa remains deeply loyal and affectionate toward Owner, showcasing the bond between pets and their humans.

The narrative unfolds through a series of short, episodic vignettes that highlight Wa's daily adventures and misadventures. These include mundane yet relatable scenarios such as Owner's attempts to diet, Wa's curiosity about household objects, and the challenges of coexisting with a cat named Maru. Wa's perspective as a dog adds a unique layer of humor and insight, as she interprets human actions in ways that are both amusing and thought-provoking. The series also touches on themes of companionship, the simplicity of life from a pet's viewpoint, and the small joys found in everyday routines.

The main characters include Wa, the sharp-witted Shiba Inu who serves as the protagonist and narrator; Owner, a kind but often clueless young woman who dotes on Wa; and Maru, the aloof and mischievous cat who shares the household. Their interactions form the core of the series, with Wa's commentary providing a humorous lens through which the dynamics of their relationships are explored. The simplicity of the plot and the focus on character-driven humor make the series accessible and engaging, appealing to fans of lighthearted, slice-of-life anime.