Muco is a cheerful, somewhat simple-minded Akita dog. He belongs to Komatsu-san, a professional glassblower, and shares a home centered around Komatsu-san's glassblowing studio and residence. Muco's days unfold through ordinary domestic activities and interactions.

He regularly greets Komatsu-san's friends: Ushikou-san, a frequent visitor to the local bar, and Bōda-san, the bar's owner. Bōda-san's daughter, Rena-chan, is another familiar human presence. Muco also encounters Shinohara-san, Komatsu-san's love interest, and interacts with Dr. Mutō, the local veterinarian.

Muco's experiences are episodic, focusing on routine events rather than a continuous story or significant personal change. His perspective often observes the lives and relationships of the humans around him, particularly Komatsu-san's daily work and social life. Muco remains a consistent, unchanging presence in Komatsu-san's life and community, providing companionship and incidental humor through his reactions and behavior.