Daydream Dragons are the hosts of daydreams and fantasies. They spend the majority of their time sitting on clouds, dropping daydreams down into the minds of people passing by. Humans who live near Daydream Dragons must be especially careful not to let their thoughts wander, or they could end up spending hours or even days in a trance-like waking dream state.

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.

Koriyuu's lineage is rich with diversity, stretching back to include anything from Deep Sea dragons to the long-extinct Bright Pink dragon. Koriyuu is very proud of his heritage and often lords it over other dragons, sparking fights. He is a bit stuck up and doesn't get along well with others. From a young age, he developed the idea that he was special, and expects to be treated as such by all he meets.