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.

Tsumetai Mizu is a distant dragon who likes to do his own thing. He is named Cold Water by the way he acts. Often times he can be seen being followed around by Kosoku Sui (his polar opisite) who is constantly bugging him, even if he doesn't apper to mind to much. The only persondragon known that Tsumetai will soften up around is Fukia and BloodMaster (though it is a mystery why).

Tsumetai was BloodMasters 5th (11.23.09) dragon and acts kind of brotherly to BlooMaster. He was found as an egg in a lake that was being to dry up so BloodMaster took him.