Sunset Dragons are closely related to sunrise dragons. However, their behaviors differ greatly. Sunset Dragons generally live alone or in small packs. They are more active in the evening, hunting and performing all of their daily tasks as the sun sets.

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.

King of Sunsets is the guardian of the Sunset Cave, an otherworldly place high in the mountains by the sea. It is one of the four Sun caves, places that maintain the order of the day's light. The other three are the Sunrise Cave, the Noonday Cave, and the Midnight Cave. They are filled with brilliant, shining light corresponding to the time they represent, and are guarded by a corresponding breed of dragon. (The midnight cave is completely and utterly dark) It is the task of the guardian to open the entrance the perfect amount at the right time each day to fill the world with beauty. This duty requires an incredible amount of skill and patience, and the ability to deal with loneliness for years at a time.

Not even the guardians have the physical stamina to reach the cave from the mountain's base, so many become suicidal from loneliness. However, he was lucky enough to be born at a time when there were many young females on the mountain, and quickly found his mate, Whitefyre.