"Kitakubu Katsudō Kiroku" is a slice-of-life comedy manga that centers around the daily activities of a high school club known as the "Past Activities Club." The club, which lacks a clear purpose or defined activities, is composed of five members: Natsuki, the straightforward and slightly mischievous protagonist; Akane, the eccentric and unpredictable club president; Kana, the quiet and reserved member with a sharp wit; Botan, the cheerful and somewhat naive first-year student; and Chizuko, the mature and level-headed vice president. The group spends their time engaging in absurd, nonsensical conversations and participating in random, often humorous activities that defy logic.

The narrative unfolds through a series of episodic chapters, each focusing on the club members' interactions and their attempts to find meaning or entertainment in their seemingly purposeless club. The humor arises from the characters' exaggerated personalities and their ability to turn mundane situations into bizarre and comedic scenarios. The clubroom serves as the primary setting, where the members frequently engage in wordplay, surreal discussions, and playful arguments. Despite the lack of a central plot, the series maintains a lighthearted and whimsical tone, emphasizing the camaraderie and quirks of the group.

Throughout the manga, the characters occasionally interact with other students and faculty, further highlighting their eccentricities and the contrast between their unconventional behavior and the more structured environment of the school. The series does not aim for deep character development or dramatic arcs but instead focuses on delivering consistent humor and absurdity. The interactions between the club members, their unique dynamics, and their ability to find joy in the trivial aspects of life form the core of the narrative. "Kitakubu Katsudō Kiroku" is a comedic exploration of friendship and the unpredictable nature of everyday life, presented through the lens of a group of high school students who embrace the absurd.