Agetarō Katsumata is the main protagonist of his story, a young man who finds himself at a crossroads between tradition and a vibrant new passion. He is the third-generation heir to Shibukatsu, a tonkatsu restaurant located in the heart of Shibuya, Tokyo. At the outset, Agetarō is presented as an unenthusiastic apprentice, helping his family by performing mundane tasks like shredding cabbage and making deliveries, all without a clear sense of direction or personal drive. His life is defined by duty and repetition, and he approaches his work with a sense of obligation rather than genuine excitement.

His personality is characterized by an infectious, electric enthusiasm that awakens when he accidentally discovers the world of nightclub DJing. Tasked with a late-night food delivery to a local club called Club Box, Agetarō is invited inside and is immediately transfixed by the atmosphere of flashing lights, dancing people, and energetic music. This experience is transformative. Witnessing a performance by a legendary American DJ named Big Master Fly, Agetarō has an epiphany: the rhythmic actions of a chef frying tonkatsu and a DJ mixing records are fundamentally similar. This realization sparks an intense and focused motivation. He is not depicted as a cynical or rebellious youth; instead, he approaches his new ambition with a positive, almost naive, and wholeheartedly earnest attitude. His goal is not to abandon his family's business but to master both disciplines, aspiring to become a man who can fry the perfect pork cutlet and excite a crowd on the dancefloor.

In the narrative, Agetarō serves as the driving force, bridging the gap between the traditional tonkatsu shop and the modern club scene. His role is that of an eager student, and his journey is one of self-discovery and skill acquisition. He does not possess any natural talent for DJing, and his early attempts are clumsy and uninformed. His primary motivation leads him to form a crucial relationship with DJ Oily, a disheveled and overlooked DJ whom Agetarō saves from hunger. In exchange for a daily supply of lard, DJ Oily agrees to teach Agetarō the fundamentals of DJing, becoming his mentor. This relationship is mutually beneficial and forms the core of his development. Agetarō also has a supportive but often bewildered group of friends from the neighborhood, as well as a strict but respected father, Agesaku, whose lessons about tonkatsu-making frequently find parallels in Agetarō's DJ education. Other key relationships include his encounters with rival DJs who challenge him and the various quirky regulars at both the restaurant and the club.

Throughout his journey, Agetarō demonstrates significant development. He transitions from a disengaged boy going through the motions into a young man with a clear, self-defined purpose. He learns to see his family's craft in a new light, finding value and artistry in the rhythms and sounds of the tonkatsu kitchen, from the bubbling of oil to the pounding of meat. This ability to find parallels between two seemingly unrelated worlds is his most notable ability. He does not possess superhuman skills; instead, his strength lies in his unwavering determination, his positive outlook, and his capacity to translate the physical techniques of cooking into the creative techniques of a DJ. He grows by facing failures and small victories, slowly developing his own unique style that is a direct fusion of his dual identity as a tonkatsu chef's son and an aspiring club DJ.