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.

Unlike his siblings who hold positions in the Sylvain family's Black Dragon combat, rescue, and guard teams, Hiraji stays near his home most days rather than going on missions. He's set up a comfortable niche for himself by providing a claw-care service for the Black Dragon teams, making sure that everyone's claws are healthy and well-suited for any kind of battle. Furthermore, Hiraji not only sharpens and polishes claws, but also experiments with layers of mana placed over the nails, which allows for all sorts of spells to be quickly cast in a pinch. Hiraji's personal unconventional form of fighting has made him a favorite at the local dueling festivals, where he's become known for his entertaining and wildly unpredictable magic cast with just a snap of his fingers.