The Ryu is a Asian Lung which lives in Japan. It is shorter than the Chinese Lung presumably due to having less available space. Even when out of their natural habitat they can be distinguished by its possession of three toes as opposed to the Korean's 4 or the Chinese's 5.
Much like to Korean Yong they spend the winter in volcanic springs and so their cave is always near such springs. A problem this causes is that the springs are also occupied by macaque monkeys who take their space and steal their eggs. The Ryu's solution is simple: eat the monkeys.
They will also eat fish and waterfowl like other Asian dragons but their diet stretches as far as wild boar which they try to kill with their claws although when threatened will change to using fire. Another interesting thing is that, despite almost all dragons being strictly carnivorous, do not just like cherries but have a unchangeable fondness for them and will chose them over meaty food stocks.
Another thing which they enjoy is writing and reading which they share with any local monks. They can write and read in many languages and are particularly passionate for complicated and ancient ones. So if you see a stone in the orient which looks like it has Linear A carved in to it then their's probably a Ryu about.
The males can be noted for their lack of tail plumage.
These dragons are rare, and hardly ever seen in the wild. Almost none are bred in captivity either.
Top tips: Do not bathe with them unless you want to end up as kibbles and dragon bits!!!