Being My Archrival's Lackey

Chu Feiqing used to be Yue Changning's enforcer, beating up Yin Huailu on his behalf. One day, Yin Huailu suddenly told him, "You've changed masters."

Yin Huailu: "I remember you made me crawl through a dog hole three times."

Chu Feiqing: "...Master, let's talk this out."

Yin Huailu: "Oh?"

Chu Feiqing: "...Woof."

So this is the story of a tree spirit becoming his nemesis's lackey, and joining his current master (husband) to vanquish demons, uphold justice, and keep the people safe and prosperous. An episodic story with a faux mystery-and-deduction slant.