Natural 2: Duo

Chisato and Kuu lost their parents years ago and were taken in by an old man and his grandson. The two girls formed a close bond with the boy, spending their days together in a peaceful rural home. However, the grandson eventually left without explanation, and the sisters were left with only memories of their cherished "Onii-chan."

Years later, Chisato unexpectedly encounters the boy who once meant everything to her. Now grown, he has returned, and their reunion stirs up long-buried feelings. As they reconnect, old emotions and new desires collide, forcing Chisato to confront the unresolved past and the complicated nature of their relationship. The fragile peace of their lives is tested as hidden tensions and unspoken truths begin to surface.