Seasonal Dragons take on the characteristics of the season during which they are born. Thus, eggs that are laid in spring match the pink flowers and green buds of spring, and those that are laid in the summer grow to depict the bright green of the forest trees and the yellow of the sun. Eggs laid in autumn display the bright colors of leaves falling from trees, and those that are laid during winter take on the appearance of the icy snow.

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.

Osugi "no Suzu" is the elder sister of Kasaru. Many male dragons desire to mate her, but she rejects them; all they want are her genes. She wishes for a less humanly (as humans are beasts) dragon to arrive, yet none of the suitors seem to learn.<br/>Aside from these events, Osugi is very motherly and caring towards her brother. She immediately stopped protecting him when he matured, and introduced him her friend Tsuonie (another Seasonal). Osugi did so to protect Kasaru from the same fate as hers (having suitors).