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.

Hitoshizuku's name, meaning "a drop of water", does not only describe his natural environment, but also reflects his personality. Calm, intelligent and strong-willed, he is nothing but a portrayal of a born leader. Despite being a typical water-dragon, reigning over the lake he was born in, he spends nearly more time on the surface than in the depths; the reason for that is his faithful mate Shirome.

Being the eldest dragon in the area, and well-known for his wisdom, Hitoshizuku is frequently visited by younger dragons, seeking advice, eager to prove themselves worthy of the title "dragon".