"Seito Kaichō ni Chūkoku" centers on the student council of Hekiyou Academy, a prestigious all-girls school, and the dynamics between its members. The series primarily focuses on Rin Shima, the diligent and responsible student council president, and her interactions with the other council members, particularly the mischievous and flirtatious vice president, Aoi Kiriya. Rin is determined to maintain order and uphold the school's traditions, but her efforts are frequently challenged by Aoi's unpredictable behavior and tendency to push boundaries.

The narrative explores the daily lives and responsibilities of the student council as they navigate school events, administrative tasks, and interpersonal relationships. Rin often finds herself in situations where she must rein in Aoi's antics, which range from playful teasing to more disruptive actions. Despite their contrasting personalities, Rin and Aoi share a close bond, and their interactions form the core of the series. The story also delves into the lives of other council members, such as the serious and stoic secretary, Minami Nanase, and the cheerful treasurer, Chikage Ueshita, who each contribute to the council's dynamics in their own way.

Themes of friendship, responsibility, and the challenges of leadership are woven throughout the series. Rin's commitment to her role as president is tested as she balances her duties with her personal feelings, particularly her growing affection for Aoi. The series blends lighthearted humor with moments of introspection, creating a balance between comedic and heartfelt elements. The episodic structure allows for a variety of scenarios, from organizing school festivals to addressing student concerns, all while highlighting the evolving relationships within the council.

"Seito Kaichō ni Chūkoku" presents a slice-of-life portrayal of high school life, emphasizing the importance of teamwork and mutual understanding. The characters' growth and interactions drive the narrative, offering a glimpse into the complexities of leadership and camaraderie in a school setting.