Originating from a single species that thrived in ancient times, Xenowyrms have become an incredibly diverse breed whose appearances vary depending on their habitats. Each Xenowyrm subspecies is heavily reliant on the power of different types of mana, making them powerful magic users. Ke’maro are a vicious, opportunistic variety of Xenowyrm. They hunt down any prey they see, trapping them with their coils and the soft, fleshy tentacles they keep stored under their skin. Their terrifying appearance and toxic saliva along with their method of hunting and trapping prey has lead to many legends and stories that warn against traveling alone in the vast volcanic wastelands they call home.

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.

When Nihastrai came to the Open Medical University, her plan was to use it as cover and learn to hunt other dragons. Once there, she discovered Azurellius's kitchen and her plans changed. The pargulus was too small to bother hunting, so Nihastrai watched him use knives and fire to process food for various species. Nihastrai became fascinated by what other kinds of dragon eat. Instead of predating her peers, she began studying the destructive processes involved in digestion and has graduated as a dietician. If she suspects clients of lying about following the diet she recommends, she has a special "dance" with her tentacles that is sure to cause nausea and usually allows her to get a sample of what they're actually eating. Her death magic only sees use on her off days, when she often hunts aurochs bulls or wild behemoths for sport.