Pillow Dragons are covered in enormous amounts of fur affectionately referred to as fluff. Despite their deceivingly large size, they can still fly even with such tiny wings because their bodies are remarkably light. Pillow Dragons have a habit of sleeping for up to eighteen hours a day, waking only in short bursts. During their few waking hours, they take the time to hunt for prey. Once a pillow dragon becomes an adult, its fur grows very slowly. Pillow dragon fur is used to make very expensive and valuable cloth known as “dragon cashmere.”

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.

Compared to most Pillow Dragons, Ko (or, affectionately, Koko) is rather active. Sure, he may rarely venture from the cave he lives in, but Kamukura, his fellow resident, provides him with everything he needs in return for his company. And his company requires being awake significantly more than 6 hours a day. When he is awake, Ko is a strange case. He's intelligent, remarkably so, but prefers to keep it to himself. He doesn't have an awful lot of friends or even, as he says, a family to go back to. When he does actually go out to view the world, he takes things at his own pace. While he's perfectly capable of analyzing and taking in things quickly, he enjoys seeing what he calls "beautiful things." He's often attempted to convince Kamukura to do the same, but is always met with nothing more than a snort and Kamu wandering off to go do something productive.