"Drifting Home" centers on a group of childhood friends who find themselves in a surreal and mysterious situation after exploring an abandoned apartment complex slated for demolition. The story begins with Kosuke and Natsume, two former close friends who have grown distant over time, reuniting with their group of friends to visit the apartment building where they once spent much of their childhood. The building holds sentimental value for them, as it was a place of shared memories and camaraderie. However, their nostalgic trip takes an unexpected turn when the building is suddenly swept away by a strange phenomenon, leaving them adrift in a vast, endless ocean.

As the group struggles to comprehend their predicament, they must navigate the challenges of survival while confronting unresolved tensions and emotions among themselves. The dynamic between Kosuke and Natsume becomes a focal point, as their fractured friendship is tested by the harsh realities of their situation. Other key characters include Noppo, a mysterious boy who appears to have a connection to the building, and various members of the friend group, each contributing to the group's dynamics and survival efforts.

The narrative explores themes of loss, growth, and the passage of time, as the characters grapple with their pasts and the uncertain future ahead. The surreal setting of the drifting apartment complex serves as a metaphor for their emotional states, with the ocean symbolizing the vastness of their fears and the unknown. Throughout the series, the group encounters strange and otherworldly phenomena, which force them to confront their deepest insecurities and fears.

As the story progresses, the characters work together to uncover the truth behind their predicament and find a way to return home. Their journey is marked by moments of tension, camaraderie, and self-discovery, as they learn to rely on one another and confront the unresolved issues that have shaped their relationships. The series balances its emotional core with elements of mystery and adventure, creating a narrative that is both introspective and engaging.