Deep Sea Dragons, as their name suggests, spend most of their time in the darkest depths of the sea. They have a bioluminescent dorsal spine that serves to attract prey and communicate with their own kind. As with many deep sea animals, they generally eat whatever they can manage to bait. They rarely leave the ocean floor, surfacing only during breeding season. When they do choose to travel to the shallower depths, they avoid bright lights and will only come up far away from shore.

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.

Nillu is seen as a loving and caring fellow, always going out of his way to take care of unwanted eggs. Nilliu is rarely seen without an egg carefully nestled in his mouth. But there is an dark and unknown side to his egg-sitting. Lazy Nillu only cares for eggs that are just about to hatch so he actually doesn't have to do any work. And because he lives deep down in the ocean, many the eggs crack from the incredible water pressure. For the hatchlings that do make it out of their eggs, a good number perish right off the bat because they are under water. All in all, the majority of the eggs that Nillu looks after do not survive. For every living dragon, there were at least ten more that did not make it. If you look at the large number of living orphaned dragons, you will boggled by the massive numbers that must have died. Though Nillu's caretaking is bad enough, you have to wonder where exactly he gets all of the eggs, since you don't exactly find eggs out floating in the ocean.