"Dirty Pair: Affair on Nolandia" is a two-episode OVA that serves as a continuation of the "Dirty Pair" franchise, originally based on the light novel series by Haruka Takachiho. The story is set in a futuristic universe where the protagonists, Kei and Yuri, are agents of the World Welfare Works Association (WWWA), known as the "Lovely Angels." Despite their reputation for causing collateral damage, they are highly skilled operatives tasked with resolving crises across the galaxy.

The narrative centers on the planet Nolandia, a resource-rich world embroiled in political turmoil. The ruling family, the Nolands, faces internal strife as factions within their government vie for control. Kei and Yuri are dispatched to investigate the assassination of a key political figure, which threatens to destabilize the planet further. Their mission is to uncover the truth behind the assassination and prevent an all-out civil war.

As the story unfolds, Kei and Yuri navigate a complex web of political intrigue, encountering various factions, including revolutionaries, corporate interests, and corrupt officials. Their investigation leads them to uncover a conspiracy involving a powerful energy source known as "Nolandium," which is central to the planet's economy and the conflict. The duo must confront not only external threats but also their own limitations as they work to restore order.

The OVA maintains the signature blend of action, humor, and sci-fi elements characteristic of the "Dirty Pair" series. Kei and Yuri's dynamic partnership is highlighted through their banter and contrasting personalities—Kei is bold and impulsive, while Yuri is more analytical and composed. Their interactions provide levity amidst the high-stakes narrative, balancing the tension of the political drama with moments of comedic relief.

The plot is driven by a series of action sequences, including chases, shootouts, and confrontations with hostile forces, showcasing the protagonists' combat skills and resourcefulness. The story also delves into themes of loyalty, betrayal, and the consequences of unchecked ambition, as various characters' motivations are revealed. The resolution ties together the political and personal stakes, offering a satisfying conclusion to the central conflict while leaving room for the broader implications of the events on Nolandia.