Brimstone Dragons live in dry arid areas such as deserts where they feed mainly on sheep, goats and the occasional camel. Their favorite habitat is ideally situated close to the wastelands around active volcanoes. This is due to an important part of their diet—sulfur, which they obtain from deposits near volcanic gas vents. Instead of fire, these dragons use the sulfur they ingest to create a noxious gas which they store in their large throat pouches. When in danger, this gas is released in a large cloud. They also eat other mineral rich substances—including charcoal—and will drink the mineral rich (but slightly acidic) water commonly found in deserts and volcanic regions.

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.

Ustrina is stuck in a cycle of depression. She has been for most of her life. When she was young, she was stolen from the nest (which is what Eden told her). She was either picked on or avoided by her fellow hatchlings growing up. When she became an adult, she was befriended by Aleck Brizian. They were seen together so often that some of the more compassionate dragons became worried when they weren't together.

Then he was killed, and revived as Aleck Inmortuorum. She was devastated—not because he was alive, she was supremely thankful for that, but because he no longer recognized her. He attacked her—his best friend—the moment he saw her. The only reason she wasn't dead (or another zombie) was because Ian stepped in.

Ustrina was stolen from her family. She was abused as a hatchling. And her sole friend as an adult has turned into an uncaring creature.

She has been stuck in a cycle of depression all her life, and sometimes, it just seems like too much.