"The Planet with Sleeping Dragon" is a science fiction manga that explores themes of survival, human resilience, and the mysteries of an alien world. The narrative centers on a group of astronauts who crash-land on a distant, uncharted planet after their spacecraft malfunctions. The planet, initially appearing desolate and lifeless, soon reveals itself to be teeming with strange flora and fauna, as well as remnants of an ancient, advanced civilization. The astronauts must navigate this hostile environment while uncovering the planet's secrets.

The protagonist, a skilled but emotionally reserved engineer named Kaito, emerges as the de facto leader of the group. Alongside him are Aiko, a biologist with a deep curiosity about the planet's ecosystem; Hiroshi, a pragmatic and resourceful pilot; and Yumi, a medical officer grappling with the psychological toll of their predicament. As they explore the planet, they encounter a massive, dormant dragon-like creature embedded in the planet's crust, which appears to be the source of the planet's unusual energy signatures. The group debates whether to awaken the creature, fearing it could either be their salvation or their doom.

The plot unfolds as the astronauts uncover fragments of the ancient civilization's history, suggesting that the dragon was once revered as a guardian but later sealed away due to its destructive potential. Tensions rise within the group as they face internal conflicts, dwindling resources, and the planet's increasingly hostile wildlife. The story delves into the moral and ethical dilemmas of survival, the consequences of human curiosity, and the blurred line between myth and science.

As the narrative progresses, the astronauts discover that the dragon is not merely a biological entity but a sentient being with a connection to the planet's core. The climax revolves around their decision to either awaken the dragon to harness its power or leave it dormant to prevent potential catastrophe. The manga concludes with an open-ended resolution, leaving the fate of the characters and the planet ambiguous, emphasizing the uncertainty and complexity of their choices.