"Ghost Sweeper Mikami" centers on Reiko Mikami, a skilled and ambitious ghost sweeper who operates a business specializing in exorcising spirits and supernatural entities. Mikami is driven by a desire for wealth and success, often prioritizing lucrative jobs over moral considerations. Her work frequently brings her into conflict with various ghosts, demons, and otherworldly beings, which she confronts with a mix of cunning, brute force, and specialized tools like her signature weapon, the Gozyu Tenrou Rod.

Accompanying Mikami is her assistant, Tadao Yokoshima, a perverted and cowardly teenager who often serves as comic relief. Despite his flaws, Tadao occasionally proves useful in their missions, though his antics frequently lead to trouble. The duo is also joined by Okinu, a young ghost girl who becomes a loyal companion after Mikami initially attempts to exorcise her. Okinu’s presence adds a layer of emotional depth to the series, as her backstory and connection to the spirit world are explored.

The episodic structure of the series features Mikami and her team tackling a variety of supernatural cases, ranging from haunted houses and cursed objects to malevolent spirits and powerful demons. Each case often blends humor, action, and horror, with Mikami’s no-nonsense attitude contrasting sharply with Tadao’s bumbling nature. Overarching plotlines occasionally emerge, particularly involving powerful entities or rival ghost sweepers, but the focus remains on the episodic adventures.

Themes of greed, morality, and the coexistence of humans and spirits are woven into the narrative, often explored through Mikami’s interactions with clients and supernatural beings. While Mikami’s primary motivation is financial gain, her actions sometimes reveal a deeper sense of justice and compassion, particularly when innocent lives are at stake. The series balances its comedic and action-oriented elements with moments of genuine tension and emotional resonance, creating a dynamic and engaging viewing experience.