Royal Crimson Dragons are so named due to their massive size and confident, regal bearing. Most of the time they are laid back, ignoring non-prey creatures smaller than themselves, although they will occasionally take fresh kills from other dragons as a reminder of their place in the social order. Although there are few other dragons large enough to pose a threat to Royal Crimsons, they have little tolerance for potential rivals and will fiercely defend their territory from such intruders.

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.

Runio is the self-proclaimed leader of the harem. He is snarky, but not insensitive. Being much larger (and lazier) than anyone else, he steals a sizable portion of meat from the others, who can barely stand up to him. Runio, however, is deathly afraid of Cidni, a Magi Dragon, who keeps Runio in check with his magic. Cidni has forced Runio to protect the eggs during Ritra's sleeping hours in exchange for stealing the dragon's food.

Due to his irritating nature, Runio does not have a mate or children.