Furry - Oil to me seemed like it was almost exclusively trained on Chunie (aka Hun). It would even constantly try to dump their signature into a low corner just like your examples show, lol.

https://www.furaffinity.net/user/hun/

It was the odd one, because the other three furry filters clearly used the same LoRa (no idea what that one's background was), and only changed a bunch of hidden prompts to give the images a corresponding look. But then again Oil was also a late addition.