Surface Contamination

Surface Contamination is the impurity in the surface environment that makes it poisonous to Agarthans and has nearly driven the gatekeepers out of their minds. It shapes the story’s boundary between surface and subterranean life: the surface is not simply a destination an Agarthan can choose to visit, but a danger that limits where people can go and whom they can accompany.

Nature and Effects

The contamination is described as an impurity on the surface. A boy explains that gatekeepers once guided humans, but that by now the surface impurity has nearly driven them out of their minds. This links environmental change to the deterioration of beings that had served as guides, though the account does not specify the impurity’s origin or the exact process by which it affects them.

The surface atmosphere is also poisonous to Agarthans. The danger is stated directly when Asuna considers whether Shin could return with her: she cannot invite him to the surface because its atmosphere would harm Agarthans. The text establishes the consequence, but does not describe a particular exposure or specify how quickly the poison takes effect.

Signs on the Surface

The condition is associated with the dangerous world beyond Agartha, though the evidence does not make every threat there a direct result of contamination. When Asuna encounters a monster, the boy says it is near the end of its life and wonders whether this is the fate of those who remain on the surface. The scene makes surface survival appear precarious, without establishing that contamination alone caused the monster’s state.

Shun is also found on the surface, wearing an unfamiliar leather cloak and unconventional clothes, with a blue jewel shining on his chest. His appearance establishes that he is present in that environment; it does not explain how the contamination affects him or whether the jewel has any protective function.

Consequences and Narrative Significance

Contamination turns the surface into a material barrier between Asuna and Shin. When they part, Shin says he cannot return to the village of Canaan because doing so would sour relations with Amaurot. Asuna, in turn, cannot ask him to accompany her to the surface because the atmosphere is poison to Agarthans. The choice that follows is for Shin to go with Morisaki, leaving the question of whether the dead should be resurrected unresolved for him.

The contamination therefore gives separation an environmental cause alongside the political constraint Shin names. It also makes the surface’s danger more than a distant warning: the account connects it to the failing gatekeepers and to the limits on where an Agarthan can live or travel. The specific source and full extent of the impurity remain unstated.