It was the seventh month, when the veil between worlds grows thin. Wang Sheng, a young scholar on his way to the provincial examinations, met a woman weeping by the roadside under the moonlight.

She was beautiful beyond mortal measure — skin like jade, eyes dark as ink pools.

"Miss, why do you weep alone at this hour?" he asked.

"My husband has cast me out," she said, her voice like wind through bamboo. "I have nowhere to go."

Wang Sheng offered her shelter in his study. His wife protested, but he would not listen. For days, the woman remained. Wang neglected his books, his wife, his duties.

One night, a Taoist priest stopped him on the street. "Young man, what evil have you invited into your home?"

"None. Only an abandoned woman."

The priest sighed. "Go home. Look through your study window. But do not enter until you have seen the truth."

Wang returned. Peering through a crack in the paper screen, what he saw froze the blood in his veins.

A monstrous creature sat at his desk — green-faced, fanged, its body covered in bristling hair. On the bed lay a human skin, painted exquisitely with the features of the beautiful woman. The creature lifted the skin, shook it out like a robe, and stepped into it — becoming the woman who had wept in the moonlight.

Wang fled. The priest gave him a fly-whisk dipped in sacred water. "Hang this above your door."

That night, the painted-skin demon came. She hissed at the fly-whisk. Then she reached through, tore it from the doorframe, and entered.

Wang Sheng's screams woke the household. When his wife rushed to the study, all she found was her husband's body — his chest torn open, his heart missing, his face frozen in terror.

This is the first tale. There are four hundred and ninety more. Each one a door. Each one a warning.