Keiji Tokiwa is a first-year student in the Department of Dairy Science at Yezo Agricultural High School. He is recognizable by his sharp, three-dimensional eyes and his dark hair, which he ties back into a single ponytail. As the eldest son of a family that operates a poultry farm, Tokiwa has been raised with the expectation that he will one day take over the family business, a path that led him to enroll at the agricultural school through a recommendation.

Tokiwa has an energetic and chaotic personality, often acting on impulse without fully thinking through the consequences of his actions. While he is generally friendly and well-meaning, his tendency to jump to conclusions and his lack of academic focus frequently land him in trouble, making him a common source of comedic relief within the story. Despite being portrayed as one of the less academically inclined students, particularly struggling with subjects like mathematics, he is far from unintelligent in practical matters. Tokiwa is an observant individual who is quick to offer help to his friends when they genuinely need it, and he can occasionally come up with surprisingly good ideas, such as effective labeling strategies for selling sausage products. However, his creativity also extends to bizarre and ill-conceived plans, like his infamous "boys bath yogurt," which consistently earns him physical punishment from his peers. This role as a frequent target of comedic violence has earned him a reputation as the group's designated butt-monkey, a status that becomes a running gag throughout the series.

Tokiwa’s primary motivation is grounded and clear from the start: to gain the knowledge and skills necessary to manage his family's chicken farm. This practical goal shapes his actions and contrasts with the protagonist, Hachiken, who arrives at the school without a clear vision for his future. In the classroom and during hands-on training, Tokiwa excels in areas related to animal husbandry, drawing on a lifetime of experience. His proficiency is most notable when working with poultry, where his speed and precision in tasks like collecting eggs from battery cages immediately impress his city-raised classmate, Hachiken. He also possesses a deep, almost instinctual understanding of chicken anatomy and behavior, demonstrating a level of expertise that book learning alone cannot provide.

Within the social structure of the first-year students, Tokiwa is a core member of the main group, often working alongside Hachiken, Ichiro Komaba, Shinnosuke Aikawa, and Tamako Inada. He shares a particularly close friendship with Komaba, and the two are often seen together. Despite frequently being a source of frustration for him, Tokiwa relies on Hachiken for academic help, constantly seeking his assistance with studying. He is also an active member of the school's karate club. His family background becomes a significant point of connection later in the narrative, as the Tokiwa family hosts Hachiken's father for dinner, highlighting the bonds formed between the students' families within the agricultural community.

Throughout the series, Tokiwa's role is primarily that of a supportive and often humorous friend whose practical skills ground the more idealistic or uncertain characters. While he does not undergo a dramatic personal transformation, his development is seen in his consistent application of his farm-raised knowledge to schoolwork and his reliable, if sometimes chaotic, presence within his friend group. His notable abilities include not only his expertise in poultry farming but also a peculiar talent for spreading rumors, particularly incorrect ones about Hachiken, which often circulate through the entire school with remarkable speed. These traits combine to make Tokiwa an integral part of the story’s heart and humor.