Olive Dragons are a small, forest-dwelling breed, rarely growing much larger than the average sheep. When alarmed, they can erect a long row of venomous spines on their back, serving to warn any potential predators that Olives are not a good choice for a meal. While not strong enough to kill anything larger than a small deer, their venom causes an extremely painful reaction and necrosis at the bite site, sometimes causing the flesh to rot and limbs to fall off.

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.

Cave-born and abandoned as an egg, Urameshi holds an inherent indifference for the rest of the Sylvain clan. He prefers to spend his time in the biomes, living a nomadic lifestyle and eating whatever food he is able to find on his own. When the weather forces him to, Urameshi will return to his living space in the clan caves to rest. He knows no one will bother him there, because the heavy scent of rotting leaves he enjoys keeps others away. He has a habit of gnawing low-hanging tree branches, and often kills trees unintentionally with his venom. As such, whenever a family member is looking for him, they need only look for a trail of rotting trees.