I’m Just a Siscon, So How Did I Become the Corpse Ancestor?

The protagonist, Xiang Yang, was adopted as a child by a family in Ling Village. This was the only family living in the village, and they were coffin bearers. Every other house held coffins sealed with inked carpenter's lines. One special coffin had to be moved every ten years to a place of extreme yang energy, then buried upright three inches into the ground to divide yin from yang. Exposed to sunlight, it could absorb yang energy and suppress the thing inside. But an ancestral rule forbade anyone in that place from going out at night for ten years. One night, while Xiang Yang was out, two Taoist priests arrived to investigate the source of the curfew that had taken hold in the city. They accidentally injured his younger sister. Xiang Yang loved her more than life itself. He closed his eyes, and yin energy spread. When mortals close their eyes, demons and gods appear