"Hyakko" is a slice-of-life anime set in the fictional Kamizono Academy, a sprawling high school known for its labyrinthine layout and diverse student body. The narrative centers on Ayumi Nonomura, a shy and reserved first-year student who struggles to navigate the school's confusing hallways. On her first day, she encounters Torako Kageyama, a bold and energetic classmate who quickly befriends her. Torako's outgoing nature contrasts sharply with Ayumi's introverted personality, creating a dynamic that drives much of the series' humor and character interactions.

The story expands to include two other central characters: Suzume Saotome, a tall, athletic girl with a calm demeanor, and Tatsuki Iizuka, a sharp-tongued and intelligent student who often serves as the group's voice of reason. Together, the four form an unlikely but tight-knit group, navigating the ups and downs of high school life. The series explores their daily experiences, from mundane activities like finding their way to class to more significant events such as school festivals and cultural exchanges.

While the plot lacks a central overarching conflict, it thrives on episodic storytelling, focusing on the characters' relationships and personal growth. Torako's mischievous antics often lead the group into humorous situations, while Ayumi's gradual development from a timid newcomer to a more confident individual provides a subtle narrative thread. Suzume and Tatsuki, though less central, contribute to the group's dynamic with their contrasting personalities, adding depth to the interactions.

The anime also introduces a variety of supporting characters, including teachers and other students, who enrich the school setting and provide additional comedic and dramatic moments. The series balances lighthearted humor with moments of introspection, capturing the essence of adolescence and the complexities of forming friendships in a high school environment. Through its focus on character-driven storytelling and relatable scenarios, "Hyakko" offers a charming and accessible portrayal of everyday life at Kamizono Academy.