Flat-foot Washi, Weekly Short-Short Note Prompt, 454 characters

A floating city was discovered.
However, there was no one there.

Although the houses were perfectly arranged, every trace of human presence had completely vanished.

An old document picked up by an investigator read as follows.

Long ago, in a paper mill deep in the mountains, there lived a woman. The washi paper she made possessed a mysterious power. When applied to the soles of one's feet, weight would vanish, and the body would float gently into the air. However, it could only be used by those with flat feet.

Based on that technology, researchers built a city in the sky that never touched the ground. People with flat feet migrated to the sky and began to live there.

They stopped walking.
They moved by gliding with the flat-foot washi attached to their feet, and eventually, the very sensation of movement changed.
The muscles that had supported the act of 'walking' were no longer used.

Then, a child was born who did not have flat feet and could not float in the sky. No one could teach the child how to walk, so they were sent down to the ground.

Eventually, the number of people with flat feet dwindled, and they disappeared.

The city still exists in the sky today.
Empty of people, it drifts quietly through the clouds.

'That which is supported by paper will one day vanish like paper.'
That was the warning of the floating city.