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.

Rufus fancies himself. It's the fins. Someone told him that MOST of his kind have purple ones, so he struts around being self important and the other dragons throw used oyster shells at him. Not that he cares—he knows he is special. Red fins, he reasons, will attract a better class of mate. So far, they haven't attracted any mate at all—but he puts that down to the others  being in awe of him. Actually they laugh at him behind his back. Not in front of him, as they do like him to function as the cave's air conditioner—some carefully applied flattery will persuade him to flap his fins up and down like a fan, cooling the others down when necessary.

Rufus' hobby is karaoke. This brings him into direct conflict with Brancaneve, the opera diva of his clan, and as a result he has ruled her out as a potential mate on the grounds of her appalling—to his mind—taste in music. The feeling is mutual.