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.

Celestriel is one of the eldests of a noble family. He keeps a young appearance and heart even after all those centuries. Very joyful and full of energy, Celestriel is not seem with good eyes by the other eldests, who considers his actions "inappropriate" for someone of so much importance. He is like a prince among the cloud dragons.

Celestriel gave a name to his cloud—"Sweetie"—and likes to talk to it even though it never answers him. This habit makes people think he is mad, but he is just way too much talkative, enough to have conversations with clouds and other objects.