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.

A thin and gloomy beast, Mix absolutely detests his life. To prevent him from using his magic to escape, Mix's owner chained the dragon to a Cassare by the name of Acid Lingers. Because of his connection to magic itself, the deadening nature of Acid Lingers's aura has muffled Mix's mind. Once a rebellious young dragon, Mix is now seen as a very slow creature, both intellectually and physically.

Acid Lingers does not fully like his job, as he has to babysit the dulled Shadow Walker who now has the mentality of a very, very young human child. While he takes pity on the other dragon and sometimes even enjoys the quiet moments they have together, the tantrums and laziness that company the job do not make it the best.

It has to be said, however, that the Cassare strongly disagrees with the fact that his owner still makes the Shadow Walker breed with other dragons. Being chained together does not have its rewards for either of them.