Eris and Espen

This love and loneliness overflowed so much that one day, it was no longer simply emotion, but living and breathing creatures descended from the esteemed gods themselves. They named the first of these children Eris, and the second Espen--though to call them the first and second would not be quite accurate, for they were so intertwined it was unclear whether they were even separate entities.
Both shared the capabilities of their parents, holding minor dominion over the sky, land, and sea. Esteemed Taleyar and Chyrlathyn loved these children, and raised them to know their position in the world strongly. But though Eris understood her parents' teachings and readily accepted her place at their side, Espen rebelled; and for many thousands of years, Eris and Espen were in turmoil, each pulling the other away from their true self.
To protect her daughter, esteemed Chyrlathyn banished Espen. Unfortunately, it was too late, for Eris' heart had already been corrupted by her brother's darkness.