"Yoshinaga-san Chi no Gargoyle" centers on the life of Yoshinaga, a high school student who discovers a mysterious gargoyle statue in his family's garden. The statue, named Gee, comes to life and reveals itself as a supernatural being tasked with protecting the household. Gee's presence introduces a blend of comedy, supernatural elements, and slice-of-life dynamics as Yoshinaga navigates the challenges of daily life with a gargoyle as a constant companion.

The narrative explores the evolving relationship between Yoshinaga and Gee, with Gee's protective instincts often leading to humorous or chaotic situations. Despite his intimidating appearance, Gee is portrayed as loyal and endearing, forming a bond with Yoshinaga and his family. The story delves into themes of responsibility, trust, and the unexpected ways in which relationships can develop, even between a human and a supernatural entity.

Secondary characters, including Yoshinaga's classmates and family members, contribute to the story's comedic and emotional depth. Their interactions with Gee often highlight the contrast between the mundane and the extraordinary, creating a balance of lighthearted moments and occasional heartfelt scenes. The manga maintains a steady pace, blending episodic adventures with overarching character development, ensuring that the supernatural premise remains grounded in relatable human experiences.