When Water Dragons mature, they lose the ability to survive on land, entering the water permanently. They are adept swimmers and eat whatever fish are in the lake they live in. They tend to inhabit the same lake for their entire lives, although a few live in the ocean and swim all over the world.

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.

As the first-hatched, first-adult dragon on Firerubynat's property (read:scroll), Umino is the head of 'The First Four' and the unofficial leader of all the dragons here, though he has denied all responsibilities in favor of having more leisure time. He loves raising the occasional tidal wave and rainfall, the latter being a trick he learned from Rai-hime. In his hatchling days (a.k.a. before losing almost all use of his legs and land survival abilities) he was the daycare's resident prankster, and although he now resides permanently in a lake, still keeps his 'title' by finding ways to prank the rest anyway; as such, it is understandable why one of his favourite days of the year is April 1st. He has also mated with E.P., a feat the others have no idea how he managed to pull off successfully given their opposing natures.