Eighteen-year-old Bai Xiaoqi has been taught yin and yang skills such as identifying herbal medicines and drawing spells by her two grandfathers since she was a child in a courtyard in the old city. Her childhood was immersed in compasses, peach wood swords and "Yin and Yang". After he could hold the mahogany charm firmly, he began to experience the mist of the old house in the alley and the paper figures with eyes open on moonlit nights. When he drew a hot soul-soothing charm and used moongrass to calm the mourning ghost, he gradually realized the truth of what his ancestors said. Until the night of the Thunder Tribulation, he held the evil-breaking talisman and the peach wood nail, and faced the evil spirit that wanted to break the seal under the protection of his grandfathers. He was finally recognized to take over the important task, and grew up to be an Onmyoji who could stand side by side with his ancestors and support the Yin and Yang universe.
