"Sunny" is a manga series set in the 1970s at a children's home called Star Kids Home, a place where children with troubled backgrounds or absent parents are cared for. The story revolves around a group of children who form bonds of friendship and family despite their difficult circumstances. Central to the narrative is a broken-down car named Sunny, which sits in the home's yard and serves as a refuge for the children, offering them a space to dream, escape, and confront their emotions.

The protagonist, Haruo, is a young boy sent to the home after his mother abandons him. Haruo struggles with feelings of abandonment and resentment but gradually finds solace in the friendships he forms with the other children. Among them is Megumu, a quiet and introspective girl who harbors her own pain, and Junsuke, a boy with a tough exterior but a kind heart. Each child carries their own burdens, from parental neglect to abuse, and the story delves into their individual struggles while highlighting their resilience and capacity for hope.

The narrative unfolds in a series of vignettes, each focusing on different characters and their experiences. These stories explore themes of loss, longing, and the search for belonging, often juxtaposing moments of joy and innocence with the harsh realities of the children's lives. The car, Sunny, becomes a symbol of their collective dreams and a place where they can momentarily escape their hardships. Through their interactions with one another and the adults at the home, the children navigate their emotions and begin to heal, even as they face the uncertainty of their futures.

"Sunny" is a poignant exploration of childhood, resilience, and the power of human connection, capturing both the fragility and strength of its young characters as they navigate a world that has often failed them. The series balances moments of heartbreak with warmth and humor, creating a deeply moving portrayal of life at Star Kids Home.