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.

Every evening, Kurozumu makes sure all of the hatchlings in the Sylvain family have returned to the caves for the night. If a hatchling happens to have wandered off, he will search for them and escort them back to the clan's caves. He rarely interacts with family members otherwise, due to his rather solitary nature. When circumstance provides, he enjoys watching the sunsets off the cliffs of the coastal mountains.