Bleeding Moon Dragons are mostly nocturnal creatures. When outside in the sun, the small red spatters on their back grow and spread, making the dragons appear to “bleed.” It is said that the darker the shade of red, the more aggressive the dragon. Their tail barbs contain a powerful neuro-toxin which they use to subdue their prey. They are solitary creatures except when mating, preferring to dwell in the caves in mountains or other high places. Their large wingspan makes them fast flyers as well as fast runners, but they prefer to glide instead. Males are very competitive and will try almost everything to impress females, who will choose their mates based on speed and performance. Juveniles tend to form bachelor groups once fledged.

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.

Living alone in a cave can get a little boring. For about a year, PDQ Bach alleviated that by flying or running down the mountainside to the humans' town to covertly watch their behavior, being most fascinated by their music. Back at home, he began composing music based on what he learned, with a touch of humor. He still travels to town at night to leave sheet music on the bulletin pole, hoping they'll play it. All of this is in secrecy; no dragon knows PDQ Bach does music in addition to the usual business of Bleeding Moons. His den is filled with makeshift instruments and stacks of compositions.