Shadow Walkers are a strange breed that possess the ability to slip between the planes of reality, becoming immaterial. This allows them to hide in the shadows, either hunting from the concealment of near invisibility or evading enemies. Though they become corporeal to mate or to eat, they spend most of the rest of their lives walking in the shadows. Shadow Walkers are wary creatures, though on dark autumn evenings when the leaves fall to swirl in the chill, rain damp air, they may be seen drifting out from the shadows.

Dragons are highly-intelligent reptilian creatures that—from a human perspective, at least—appear to live forever. Many different varieties of dragon exist, each with their own unique qualities, habitats, and behavior. Adolescence in dragons is usually marked by the growth of a hatchling’s wings, although not all breeds of dragons grow wings and some breeds have other traits that indicate the beginning of maturation. In Galsreim, dragons and humans coexist peacefully.

Aethriox lives in a city entirely of dragons. He used to wander alongside Singer of Souls, until she somehow brought a soul into his body. Once he had a soul, Singer simply left him in the city without saying anything. It took some time for him to adjust, but eventually he settled into a routine life, where he worked in the city's militia. He also on occasion played with the children, but while doing so always seemed sad. It was assumed that this was because his childhood was ruined by his having been soulless.

During one of his battles, he rescued a bronze tinsel who had been used as a tool of war by a human mage. After the battle, he took her to the city and helped her learn to adjust just as he had, from wandering to city-life. Over time, their relationship grew closer, and slowly formed into one of deep love. At her asking, he trained her to fight and she began joining him on patrols. The two grew to have a skill in combat that is potentially unmatched in their city.