Royal Blue dragons are a nocturnal breed who prefer to live high in the mountains near slow-moving water that reflects the night sky. Although quite capable of defending themselves, they are peaceful by nature and will avoid a fight whenever possible.

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.

Tsukikoryuu was found in a cave years ago along with her mate, Rairyuu. She takes charge, and is the boss! She is very responsible, caring for the young ones, even those that do not biologically belong to her. She has taken over the role as each of the current egg's mother. She hardly gets angry other than with Rairyuu, but she cares for him all the same. Although Rairyuu is the male, Tsukikoryuu 'wears the pants' in their relationship.