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.

Water Kai a.k.a "Prince" of his cave, was given birth by Water Sorrow. Ever since Water Kai was born, he has been swarmed by many of the females (including his own siblings that are female). Fortunately, the other males were not bothered by this so he didn't have to get into a fight (they wouldn't dare anyways since he was the child of Water Sorrow). Even though there were many females (who had the guts to get near him) there was only one that interests him the most: Scarlet Kurosu. He thinks that since he is recognized as the prince of their cave, it's only fair if Scarlet Kurosu has an interest in him, too.