Hellfire Wyverns are so named for their foul tempers and fiery visages. Their social structure places all females above all males, due to superior physical characteristics and violent dispositions. Forced subservience of the males causes them to become vicious, petty, antisocial, and passive-aggressive compared to the aggressive and social females. However, orphaned hatchlings raised by foster parents of another species can develop surprisingly even tempers and mellow dispositions, proving that their defining unpleasant nature is, in fact, a learned behavior.

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.

Quatuor is a refined dragon, he acts as a gentleman prince would due to his upbringing in Cheimon castle. He loves to contend in fire-breathing contests and experiment with chemicals to see which one will produce the most beautiful flame. That had lead many of the torches in Cheimon castle to burn different colors of the rainbow or sparkle, or sometimes both.

Suffering the loss of her first hellfire egg, Aero felt she had to make sure Quatuor had a good life, but she did too good of a job. Quatuor grew up around other dragons, sure, but he's a bit of a mama's boy and is often overprotective of his beloved human surrogate mother.