Darkling

Darklings, also known as dark ones, were a lineage of fey that suffered a curse from the Summer Queen, forever doomed to absorb light and to suffer rapid aging from exposure to it. The absorbed light over the lifetime of a darkling was explosively released at the time of its death, destroying its body and much of its surroundings.

Society
Due to their curse, most darklings dwelt in caves or underground. Under cities, they typically worked as thieves or assassins. Despite this curse, however, darklings retained their love for beauty, and sometimes risked watching a sunset or occasionally using light to appreciate the colors in a piece of art.

It was possible for the most experienced darklings to undertake a ritual in order to become elders. The ritual consisted of applying glowing tattoos over its body, therefore releasing some of the accumulated light. If unsuccessful, the ritual was fatal. Otherwise, it resulted in a darkling elder: a taller and fairer form, similar to a grey-skinned elf.

History
It was told in legends that a seelie fey, whose real name had been erased from history, betrayed the Summer Queen. In her wrath, she cursed him and his entire house. He became known in those stories as Dubh Catha, or "Dark Crow". His descendants, and those of his house, were then known as the dubh sith, or "darklings".