There was a red-eyed city.

Only people with red eyes lived together, but one day, a blue-eyed child was born.

The red-eyed people called the blue-eyed child a witch and considered the blue eyes a symbol of the curse.

People deceived the blue-eyed child as a symbol of blessing and kept them from the city, but disposed of them on the day of his 13th birthday.

It was an act of sampling blue eyes, and people with red eyes called this act purification.