"Takamiya Nasuno Desu!" is a comedic slice-of-life manga centered around Nasuno Takamiya, a high school student who is the heir to the Takamiya Zaibatsu, a powerful and wealthy conglomerate. Despite her affluent background, Nasuno is determined to live a normal high school life, free from the trappings of her family's influence. She enrolls in a regular public high school, where she strives to blend in and experience the everyday joys and challenges of being an ordinary teenager.

Nasuno's efforts to maintain a low profile are frequently thwarted by her inherent wealth and the eccentricities of her upbringing. Her classmates, including the sharp-witted and observant Shiori Shinohara, often find themselves caught up in Nasuno's unintentionally extravagant antics. These situations range from her casual use of private jets for mundane errands to her obliviousness about the cost of everyday items, highlighting the stark contrast between her privileged life and the lives of her peers.

The series explores the humorous dynamics between Nasuno and her classmates as they navigate the cultural and social gaps created by her upbringing. Shiori, in particular, serves as a grounding force, often pointing out the absurdity of Nasuno's actions while also developing a genuine friendship with her. Other characters, such as the kind-hearted but easily overwhelmed teacher, Mr. Kurosaki, and the mischievous yet loyal classmate, Yui Sakura, add depth to the interactions and contribute to the comedic tone of the series.

Throughout the manga, Nasuno's attempts to live a "normal" life are juxtaposed with her family's expectations and the occasional interference of her butler, who ensures her safety and well-being. These moments often lead to exaggerated and humorous scenarios, such as her family's over-the-top security measures or their insistence on maintaining her elite status despite her wishes. Despite these challenges, Nasuno remains steadfast in her goal to connect with her peers on a personal level, showcasing her determination and good-hearted nature.

The narrative is episodic, with each chapter presenting a new comedic situation or misunderstanding arising from Nasuno's unique perspective on life. The humor is derived from the contrast between her wealth and the everyday struggles of her classmates, as well as her genuine but often misguided attempts to fit in. The series balances its comedic elements with moments of warmth and camaraderie, emphasizing the importance of friendship and understanding across social divides.