Dorsal Dragons are so named because they have large fins along their backs that can be raised and lowered at will. They use these fins to regulate body temperature; they raise them to cool off when they become overheated. The bright colors on the fins double as a means of attracting mates.

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.

GuMX3 got her name because she has three sets of gums. Many ask to see proof of this, which she refuses. She hates people ogling the inside of her mouth—it reminds her too much of going to the dentist's. Some say she is lying about having three gums because of this, but that is not the case—in reality, she is simply embarrassed because she doesn't brush her teeth as often as she should. Some say she has three gums because she ate the man with three buttocks, but this is also not true. She is not the man-eating kind of dragon to begin with. She got dragged along to a dental convention once, and the only good thing that came out of it for her is that she met GuMZI there. To this day, the two live toghether in a cave near the Aortic River hiding from dentists interested in their unusual mouths.