Undine Dragons are named for the water spirits with which they share territory. They have close relationships with these spirits, and are able to communicate with them. In exchange for protection and respect of their mutual freshwater homes, laid eggs are often protected by a blessing. This blessing stays with the dragon into adulthood, and with it they gain potent magical abilities. Sometimes when an Undine Dragon becomes very upset, the ground at their feet may frost over or begin to steam. They have also been observed to manipulate water directly, rerouting raindrops or creating puddles from groundwater. Undine Dragons always live near forest pools, streams, or waterfalls. Both genders take equal part in the raising of young and are very good parents—though they may not remain mated after the offspring are grown.

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.

Fierce and loyal, PlumTail's heart is never in the wrong place. Because his egg was stolen, he has not become fond of human beings, and is not too fond of other dragons either. PlumTail is very stubborn and short-tempered, but even he knows not to pick fights with dragons more experienced than him. PlumTail enjoys the water, as it is the only thing known to calm him down, and loves playing around in puddles. Though said Undine Dragons can possess potential magical abilities, PlumTail does not possess any.

PlumTail's mate is Vivid Pearl, and his son is Teal Rickety, whom he tries to toughen up every now and then.