What should the world under the desert look like?

Endless sand? Dark without light? No air? People dying from suffocation once getting in… Actually, it is more like a maze. There are a lot of zigzag tunnels and hundreds of branch roads. Some are wide and some are narrow; some lead to somewhere and some lead to nowhere.

In a wide branch road, there is a sparkling light on the wall. It might be the luminous component in the rock. In the faint light, the girl lying ...