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.

Natsu's warm and sunny personality is properly evocative of her name, which comes from a pictorial word in a distant language meaning summer. Much like her other seasonal counterparts, she enjoys spending as much time outside as she can during her season, preferring to sunbathe and frolic through flower-covered meadows instead of keeping to the (in her opinion) dreary caverns.