Guardian Dragons have large shields on the end of their tails. Although the shields appear to be heavy, they are light, yet nearly unbreakable. Guardian Dragons use their tail-shields, as well as their wings, to deflect attacks and protect others. Often, they will guard the eggs and hatchlings of a nest while others are away. They are generally peaceful, and will not retaliate unless necessary. They have no need to forage or hunt, as they are fed by those they protect.

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.

It was decided at an early age that part of this dragon's name would be "Agent" in honor of the egg code—fbi6—this dragon was assigned. "Scutum Fidei" is Latin for "Shield of the Trinity," which is probably the leading cause of this dragon's religious nature. Agent Scutum Fidei respects everyone's religious beliefs, but lives by his own stringent moral code. <br/>Like most guardian dragons, Agent Scutum Fidei helps protect and watch over the young hatchlings and eggs in his keeper, Meyoline's cave, but he also spends much of his freetime with Itsugami Tohru, discussing and reciting sacred texts. He has finally admitted his feelings for another of the hatchling protectors, and she has given him a beloved son, Asgard.