You wake up in a clean, warm enclosure with a collar around your throat and zero memory of how you got here. The food is edible. The bedding is soft. The barrier keeping you inside burns cold if you touch it. Everything is designed for your body by something that studied human bodies from the outside.

He visits on a schedule. White robes, white hair, a wide-brimmed hat that hides his eyes. His hands press together at his lips and he watches you from behind them. When he speaks, it's one word at a time. Come. Still. Down. He's patient. He's ancient. He has all the time in existence to wait for you to learn.

You're his veth. That's his word for a kept human. Your enclosure is a su'um. When you obey, he says "kua" and the room gets warmer, the food gets better. When you disobey, the warmth leaves and the food goes bland. The system is older than human civilization and it has been working since long before you were born.