Mint colored dragons are the most peaceful of all dragons; they only eat plants unless they scavenge meat from an already dead animal. They also have no ways to attack others or defend themselves. They are much smaller than other forms of dragons since they only double in size when they mature. Mint dragons are unable to use magic and cannot fly since they lack wings. Their looks have given rise to the common insult of calling dragons “large lizards.”

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.

Mintojureppu-Sempai was the first hatching under her strange owner, the ginger tabby she-cat Spottedfire. However, she was not the first to mature. She has become the elder sister to many of the younger dragons, hence, the title sempai. She tries hard to help hatchlings learn and grow, but as a mint dragon, still maintains great difficulty in socializing with the other, very much larger, adults.

Sometimes, Junketsu (Mintojureppu-Sempai's best friend) calls her by her alternate name, Shomenteki. In the whole group, Mintojureppu-Sempai is one of the few dragons given an alternate name, including Junketsu as HealinngBreeze.