Dragons are creatures with nearly unlimited life spans. They can survive for long periods of time, and no one has found a dragon that has died of old age. Adolescence 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. Once they hit adolescence, hatchlings change quickly, maturing to their full forms in only 2 years.

Dragons don't communicate with each other verbally, but they will growl to scare off predators and frighten prey. Young dragons will emit an extremely high-pitched squeal when they are frightened. To communicate, they use telepathy with each other and to speak to other creatures.

When water dragons mature, they lose their legs and the ability to survive on land, entering the water permanently. They are adept swimmers and eat whatever fish are in the lake they live in. They tend to inhabit the same lake for their entire lives, although a few live in the ocean and swim all over the world.

Koshin is amiable and loves to chat with the other residents of the Kyokos Vale. Always juggling new ideas and playing with words, he's the type who can keep a conversation going for hours without becoming repetitive or tedious. He especially enjoys storytelling, whether he's spinning tales for the hatchlings or just spreading gossip. His greatest regret is that the winding paths and pooling lakes of the Rivermere, extensive as they are, still restrict his ability to visit others. And without an audience, Koshin withers. Fortunately, his mate Sassatsu is always up for some verbal sparring, and his childhood companion Shingen is never far from the water, although it can sometimes be difficult to drag the earth dragon out of his own thoughts.