Dragonvalley is an area deep inside of Cosyland. The name may suggest differently, but Dragonvalley is actually a very calm and peaceful place. It’s where the Cosians go to get in touch with the Dragons*.
Normally, they do so in company of a Dragonguide, since it is easy to get lost in Dragonvalley. The Dragonguides can also help us to become friends with the dragons.
You can take this as a metaphor. The Dragons relate to our deeply enshrined emotional reaction potential that we all carry within us.
The Dragonguides help us to free ourselves from the (subconscious) emotional constraints that hold us back from unfolding our potential. Oftentimes, these constraints are also holding us back from sincerely living our cooperative human nature.
The people who work on freeing themselves from their constraints are called the Dragonfriends.