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.

Umi likes to spend her days floating around in the deeper areas of the ocean, occasionally investigating random debris that falls from shallower depths. Generally she just follows the currents wherever they push her, but if she sees an interesting object, she will deviate a bit to go inspect it. From pieces of shipwrecks to the occasional stone statue, Umi has pondered many odd sights and how they might have ended up in the ocean. Usually she concludes that they were obviously cursed and someone attempted to get rid of them, so she makes sure to keep her distance when she's done observing.