Sunset Dragons are closely related to sunrise dragons. However, their behaviors differ greatly. Sunset Dragons generally live alone or in small packs. They are more active in the evening, hunting and performing all of their daily tasks as the sun sets.

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.

Always soaring in the sky when the sun is setting down, she would not even land to rest, regardless how tired she is. In her point of view, the moment when the sun goes down is the best time of the day, the only thing worth to look forward to. Strangely, her love to the sun is only limited to the sunset. The sunrise and the day seems not to attract her. "The sunset is the gift of the sun before it leaves." Thinking of that quote, her owner has given her this name "Ryuubosei Sunset No Sunniva" or "Dragon Sun Setting Star, Sunniva of the Sunset".