"Nikujoku Iinchō" centers on the life of Itsuki Amemori, a high school student who unexpectedly becomes the chairman of the school's disciplinary committee. Known for his strict adherence to rules and a no-nonsense attitude, Itsuki is tasked with maintaining order and discipline among his peers. However, his role becomes increasingly complicated when he encounters a group of students who challenge his authority and test his resolve. The series explores the dynamics of power, responsibility, and personal growth as Itsuki navigates the complexities of his position.

The narrative delves into the interactions between Itsuki and his classmates, particularly focusing on his relationships with key figures such as Rina Tachibana, a rebellious yet charismatic student who frequently clashes with Itsuki, and Haruto Soma, a close friend who provides moral support and a contrasting perspective on discipline and authority. As the story progresses, Itsuki is forced to confront his own rigid beliefs and adapt to the diverse personalities and challenges within the school environment.

Themes of leadership, morality, and the balance between rules and individuality are central to the series. Itsuki's journey is marked by moments of introspection and conflict, as he learns to reconcile his duty with the need for empathy and understanding. The manga also incorporates elements of humor and camaraderie, balancing the more serious undertones with lighthearted interactions among the characters.

Through its episodic structure, "Nikujoku Iinchō" presents a variety of scenarios that test Itsuki's leadership skills and ethical boundaries. Each arc introduces new challenges, ranging from minor infractions to more significant moral dilemmas, allowing for character development and exploration of the broader implications of discipline and authority in a school setting. The series maintains a focus on Itsuki's growth as a leader and individual, highlighting the complexities of maintaining order while fostering a sense of community and mutual respect.