Big Salmon Lake These walls, they seem to call my name

Aries listened, ears perked, as the darker girl spoke. Nocturnal, was the name first spoken of - apparently a Deadric Princess, whatever that was. He didn't bother to ask, but his interest was spiked. There were beings that ruled the world? How come? The girl did not explain further, instead moving on to describe her realm. That was a word he had only recently learned. He was quite proud he had remembered it. 

The boy remained silent as the story continued, listening to the odd tale, that clearly the girl believed to be true. It must be, right? One must have a good imagination to simply make up something like that. He would have to remember the names that were told to him. Suddenly, he heard the word Blackfeather. His head lifted and he tilted his head. "I heard 'Blackfeather' before. What's it?" His mother and father had mentioned it before (not to him, but he was listening). What did it mean, and why did they always look frightened or angry when speaking about it?