After his wife passes away, Yamada, a solitary elderly man, shares his home with a capricious cat named Shima. The bond between them forms the heart of the story, as Yamada becomes utterly devoted to Shima's adorable expressions and whimsical behavior. Their quiet, everyday life unfolds through a series of seasonal episodes: lazy afternoons in sunny spots, playful chases, tender moments of companionship, and the small challenges of caring for a headstrong feline. The manga also includes additional tales, such as the daily life of office worker Kozue and a wandering stray cat named Suu. Through these vignettes, the narrative celebrates the warmth, humor, and subtle melancholy of living alongside a beloved pet.