Scimitar-wing Wyverns are a small breed, eating mainly birds and small vertebrates; as such, they lack the large teeth and heavy claws of their larger cousins. They are far from defenseless, however, and are named for the blade-like growth that forms over the first digit of their wings. The wyverns use these blades to defend themselves from any attacker. Their blades are quite strong and can cut through almost any scale or hide.

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.

Rapier Wing comes from a long-line of human-reared Scimitar-Wing Wyverns that were specifically raised to use the blade-like growth on their wings like an actual sword. Like his brothers and sisters, Rapier Wing was trained from adolescence by master swordsmen. Upon completing the training, Rapier Wing was to be sent to a local market to be sold as a guard dragon to a wealthy landowner. But en route to the market, an accident on the road caused the crate transporting Rapier Wing to fall off the wagon, resulting in the Wyvern getting left behind. By chance, he was found by members of Shield Tail and Dark Drakon's dragon herd and was welcomed into the fold. In time, Rapier Wing joined Strato Wing and Aura Glow in being the teachers of the herd's hatchlings, translating his swordsman skills into techniques the dragon hatchlings could utilize against dragon hunters or enemy dragons.