Vermillion Bird, Azure Dragon, White Tiger, and Black Tortoise?
I've been trying to research them (Google), but nothing detailed shows. 
All I get is something like - "Azure Dragon - East, Spring." What I'm looking for is stuff on how they came up, what attributes they're supposed to have, particular traits (appearance or personality).
Also, there's supposed to be a fifth creature who protects the zenith/center, and represents no season, but the change between the seasons, I think. But I don't know if it's the yellow/gold dragon, or the Qilin. I've had two different sources contradicting each other there, so if you could tell me that, that'd be great.
This is more the Chinese version than the Japanese, by the way.
All I get is something like - "Azure Dragon - East, Spring." What I'm looking for is stuff on how they came up, what attributes they're supposed to have, particular traits (appearance or personality). Also, there's supposed to be a fifth creature who protects the zenith/center, and represents no season, but the change between the seasons, I think. But I don't know if it's the yellow/gold dragon, or the Qilin. I've had two different sources contradicting each other there, so if you could tell me that, that'd be great.
This is more the Chinese version than the Japanese, by the way.
Comments
https://www.ancient-origins.net/myths-legends-asia/four-mythological-symbols-china-001792
If you're generally interested in Chinese fantasy creatures in literature there's also this as a quick reference:
https://immortalmountain.wordpress.com/glossary/chinese-bestiary/ ;