"Hōkago Teibō Nisshi" centers on Hina Tsurugi, a high school student who moves to a coastal town and joins the school's fishing club. Initially unfamiliar with fishing, Hina quickly develops a passion for the activity under the guidance of her clubmates. The series explores her growth as an angler, blending slice-of-life elements with educational insights into fishing techniques, equipment, and marine ecology.

The narrative is episodic, with each chapter focusing on a specific fishing trip or challenge. Hina and her friends, including the experienced and knowledgeable Natsumi Kurobe, the enthusiastic and competitive Oono, and the quiet but skilled Makoto, embark on various fishing adventures. These outings range from casual shoreline fishing to more competitive events, showcasing the diversity of fishing as a hobby. The interactions between the characters highlight their camaraderie and individual personalities, adding depth to the story.

The manga emphasizes the practical aspects of fishing, often detailing the preparation, strategies, and techniques required for different types of fishing. It also incorporates elements of humor and lighthearted moments, balancing the educational content with an engaging narrative. The coastal setting plays a significant role, with the natural environment serving as both a backdrop and a central theme, reinforcing the connection between the characters and their surroundings.

Throughout the series, Hina's progression from a novice to a skilled angler is evident, reflecting her dedication and the supportive environment of the fishing club. The manga also touches on themes of perseverance, teamwork, and the joy of discovering new passions, making it an accessible and enjoyable read for both fishing enthusiasts and those new to the subject.