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.

The "Dragon Dark Star" has been given the Japanese name "Yoite", which means "the wind in the night", because of her habit to hunt during the night, moving like the wind.

She is an absolute loner, hates to be in groups and possesses a solitary personality. The only moments, in which she is not alone, are the times, in which she fights or competes with other dragons. She strongly believes that only the strongest can survive and she believes that powerful dragons are granted the privilege and to treat the weaker ones like they want to. She despises dragons who are pacifists or disagree with her theory.

Furthermore, she does not forgive her parents for abandoning her to be raised by a human. Although she does not want to be part of "kaia-chan's scroll", she still shows gratitude to her, because she knows that she would have died if she did not take care of her. Therefore, even if it is rare, she only listens to her sometimes.