Black Dragons are warriors. They are strong and capable in battles of force, but also ample magic users, capable of devastating opponents with their spells. Their bright eyes give them excellent night vision, which is why they generally hunt during the night.

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.

By Black terms, Grimm is unusually happy-go-lucky, though by the standards of other dragons, he is hardly more than slightly more optimistic than others of his kind. He lives happily with his mate, Desta, with whom he has several children. Her outgoing personality has had a positive effect on him, and has softened him up since she first came to the cave. They live in a smaller pack composed soley of Black dragons, within Watari's cave. His surname means 'shadow rider' in German.