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.

Meilin used to be a conformer, until her innocence was shattered by a Noah—since then she's been living relatively peacefully, until a mysterious bottle showed up at her door. Without a tag, she tested it by scent first, and thinking it was perfume, applied it to her skin. This was one of Komui's potions, and it turned her into a water dragon. She's since been living in the lake where she'd originally thrown her crystal ball before it was destroyed.