Kisaragi Station

Description
The third world Lin Sanjiu visited.

In brief Scientists found some corrosive dark matter, played around with it, and it took over everything.

A scientist named Le Bon was the one who put forth the various theories regarding dark matter and its existence, but was ridiculed. Later when dark matter was discovered, the scientists started researching about its uses. Despite being one of the leading researchers in this field, Le Bon announced that he had found an alarming characteristic of dark matter a few years before the apocalyptic event.

Dark matter was corrosive.

Furthermore, the corrosive nature of dark matter had only became active in the recent years. Before this, it seemed that it had been latent. Different materials reacted differently to high levels of dark matter exposure and displayed different speeds of corrosion. This process was very slow, but Le Bon asserted that the materials would all be assimilated, and 98% of the object would become dark matter.

People got exposed to too much of it (by eating, breathing, etc.) and become ghosts or something along those lines.

The more corrupted by dark matter you are, the closer to the spirits you can be, so in the beginning you can’t see anything but once you get more corrupted you can.

This is why Reno and Rena corrupted their eyes.

The spirits also can’t interact with anyone not corrupted.