"Hanaukyo Maid-tai OAV" is a short anime series that revolves around Taro Hanaukyo, a young man who becomes the heir to the vast Hanaukyo estate after the death of his grandfather. Upon arriving at the estate, Taro discovers that it is managed entirely by a large staff of highly skilled and devoted maids, led by the head maid, Mariel. The maids are not only responsible for maintaining the estate but also for serving Taro, who is initially overwhelmed by their attentiveness and the luxurious lifestyle.

The narrative primarily focuses on Taro's adjustment to his new life and his interactions with the maids, particularly Mariel, who takes her duties very seriously. The maids are depicted as highly competent, each with unique skills and personalities, and they often go to great lengths to ensure Taro's comfort and happiness. However, Taro's humble and unassuming nature contrasts sharply with the opulence of his surroundings, leading to comedic and occasionally awkward situations as he tries to navigate his new role.

Throughout the series, Taro forms close bonds with the maids, especially Mariel, who becomes a central figure in his life. Their relationship evolves from a formal master-servant dynamic to one of mutual respect and affection, though it remains largely platonic. The series also introduces other key characters, such as Konoe, a stern and disciplined maid who often clashes with Taro's laid-back demeanor, and Ikuyo, a cheerful and energetic maid who adds a lively presence to the household.

The plot is episodic, with each episode focusing on a specific event or challenge within the estate, often highlighting the maids' dedication and Taro's growing sense of responsibility as the head of the household. While the series maintains a lighthearted and comedic tone, it occasionally touches on themes of duty, loyalty, and the complexities of relationships within a hierarchical structure. The OAV serves as a self-contained story, offering a glimpse into the daily life of the Hanaukyo estate and the unique dynamics between Taro and his maids.