"Papa wa Idol!" centers on the life of Shota Kurosaki, a 28-year-old single father and former member of a popular boy band, who struggles to balance his responsibilities as a parent with his fading career in the entertainment industry. After the disbandment of his group, Shota retires from the spotlight to focus on raising his young daughter, Hikari, who is unaware of his past fame. However, when financial difficulties arise, Shota is forced to return to the idol world, reigniting his career while keeping his identity as a father hidden from the public.

The narrative explores the challenges Shota faces as he navigates the demanding idol industry, juggling grueling schedules, public scrutiny, and the need to maintain his secret. His dual life becomes increasingly complicated as Hikari grows curious about his frequent absences and the mysterious "work" he claims to do. The story delves into themes of sacrifice, family, and the pressures of fame, as Shota strives to provide for his daughter while protecting her from the harsh realities of his profession.

Key characters include Shota, whose determination and love for Hikari drive the story; Hikari, an innocent and perceptive child who begins to piece together her father's secret; and Shota's former bandmates and industry colleagues, who play varying roles in his attempts to reconcile his past and present. The manga balances heartfelt moments of familial bonding with the comedic and dramatic tension of Shota's precarious double life, offering a nuanced portrayal of the sacrifices parents make for their children.