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.

Despite being in the upper half of the age range, Yarn is seen as a sort of little sister by the rest of the Pillows. She has always been blissfully naive, and the other Pillows try to preserve her innocence and encourage her to remain forever bright, bubbly, and unaware of the world's troubles. Yarn is too immature for anything too adult. For one thing, she may never have any children at all—after all, she is hardly more than a child herself, trapped in the body of a fully grown dragon. Yarn is very loved by hatchlings because she is one of the only adults they can see as their equal, and one of the only adults who loves to play. She is like a ray of sunshine, the living embodiment of all that is good in the world, the epitome of eternal youth.