Chapters 3-12 detail the transformation of Osaki Miroku, a 36-year-old unemployed, overweight, and reclusive man, into a more confident and active individual. Initially, Miroku is depicted as a shut-in, his life defined by his unemployment and the shame of being fired for his weight, despite his past competence. His only connection to the outside world is his supportive family, who insist on daily meals together.
Miroku's life begins to change when he discovers "Let's Dance" videos online. Driven by a desire to participate, he joins a dance gym. Despite his initial struggles with the physical demands, he is encouraged by a fellow gym-goer, Yoichi, who emphasizes building muscle rather than just dieting. Miroku's mother secretly researches and adjusts his diet to support his muscle gain, enabling him to keep up with the dance classes. He becomes dedicated, attending the gym five times a week and developing an interest in martial arts through online study. This newfound routine revitalizes him, gradually healing the wounds of his past.
His sister, Mihachi, who possesses perfect pitch, praises his singing voice, inspiring him to explore "Let's Sing" videos. He decides to try a solo karaoke session. Before his karaoke outing, his younger sister, Nina, cuts his hair and he shaves his beard, presenting a significantly improved appearance. At the karaoke, he enjoys singing and practicing dance moves, finding a new outlet for his passion.
Over three months, Miroku loses considerable weight, transforming into a lean, muscular individual with a stylish haircut. Despite his improved appearance, he remains unaware of the attention he garners. His striking looks, combined with his family's good genes, make him stand out. His karaoke performances, which now include singing and dancing simultaneously with professional-level skill, are accidentally uploaded online. The videos go viral overnight, leading to unexpected ad revenue.
Initially bewildered and embarrassed by his newfound fame, Miroku is hesitant to delete the videos after reading a comment from someone who found encouragement in them. He begins working for his father, transcribing meeting recordings, which allows him to earn money for his hobbies. His improved appearance, partly due to his sister's cosmetic experiments, leads to him being mistaken for a college student by his father's company receptionist, further highlighting his transformation.
His sister Mihachi reveals that his viral videos have caused a surge in membership at his gym, though the gym had to turn away new applicants. She suggests he use a hat and glasses to conceal his identity. Meanwhile, Yoichi, who runs a talent agency, is in a bind due to his roster being ill with a cold. He asks Miroku to fill in as a model for a fashion magazine shoot, emphasizing Miroku's height. Miroku reluctantly agrees, unaware that his appearance will cause a stir. During the shoot, his professionalism and kind demeanor impress the staff, and a photographer captures a pivotal image.
Later, Miroku encounters two former colleagues who mock his past unemployment. Yoichi and his niece, Fumi, defend Miroku, introducing him as a prominent model for their agency. The former colleagues are stunned by Miroku's transformation and flee. Miroku, though initially embarrassed by his past, finds solace in his family's unwavering support and their acknowledgment of his efforts. They encourage him to embrace his positive changes and stop demeaning himself.
Fumi, who had previously been inspired by Miroku's heroic act of intervening in a bar fight, is now his assigned manager. Miroku, still grappling with his newfound fame and the attention it brings, is surprised to learn Fumi will be his manager. He is also touched by her genuine admiration and her belief in his character, despite his past struggles. The chapters conclude with Miroku accepting his new path, with Fumi by his side as his manager, hinting at future developments in his career and personal life.
