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.

Merensininen is a mystical water dragon. She doesn't like to interact with other creatures, and she rarely even greets Waulish Vuoksi and other water dragons that live in her homelake. She often seems very sad and apathetic in an unexplainable, mysterious way. It is commonly thought that she misses the ocean where she once, according to the rumours, lived. No one knows why she left her home, and she never confirms anything. She is a mystery, and a popular topic among the clan's dragons, as well. Her name "Merensininen" is a Finnish word meaning "ultramarine"—literally "ocean-blue".