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.

Rebecca the Nightmare is a troublemaker of the highest order. Nightmare attempts to prank any creature that happens to cross her path. Some dragons are of the opinion that she is even worse than a Misfit Pygmy when it comes to jokes and tricks.

Nightmare is avoided by the other daydream dragons, but that doesn't bother her. She has two best friends who she knows that she can truly rely on. One is a male vampire dragon named Bloonstained Ivy, or Ivor for short. Inkskin, a female black dragon, is Nightmare's other friend. The three of them enjoy scaring hatchlings, taunting older dragons and generally getting up to no good.

Despite being a huge annoyance, Nightmare never actually tries to hurt other dragons with her mischief. She's never afraid to speak her mind. Nightmare isn't vain and doesn't care about everyone else's opinions of her. Although, nobody is really sure whether this is a good or bad thing!