Double Mouth Contract

All surnames in the world have a single soul and a single life. Only people with the surname Lu are born with two mouths. The upper mouth hides the yang position, and the lower mouth hides the yin position. A living person only has one mouth to live, and the other mouth is permanently vacant. If the vacancy is not empty, it must accept negative things. This is what the Lu family has been unable to escape from generation to generation - the counterparty ghost contract. It's not about running into ghosts, it's about being born to raise ghosts. For generations of Lu people, there must be a ghost who will accompany them all their lives, breathing the same breath, having the same fate, and living and dying together.