Legend has it that at the moment when the sun and moon alternate, light and darkness briefly overlap, which is the time when the natural barrier between the four realms is at its weakest.

If you were walking on a road lined with tall trees on both sides, you might occasionally catch a glimpse of a few swaying gray shadows among the layers of tree shadows.

Don't bother them. They usually won't approach people on their own. Occasionally, a few playful ones might try to get close. Don't be afraid or panic. Just pretend you didn't see them and walk away naturally. They'll get bored and leave on their own. If they refuse to leave, just stomp your feet and say loudly three times, "Go home!" and they'll stop bothering you.

Standing where the shadows of the sun and moon overlap, pick up a leaf and hold it in front of your eyes, take nine steps west, and turn around once, and you will reach a place called the Yin-Yang Boundary.

This place is quite similar to a ghost market in the human world. It appears in the dead of night and disappears like morning mist at dawn, coming and going without a trace, with no one managing or organizing it.

The things sold are not limited to physical goods, but more importantly, information. Wherever people can go, there is information that can be bought. Therefore, the Yin-Yang Realm is a mixed bag, and all those who enter and leave must wear masks to cover their faces so that their true identities cannot be seen.

On this day, the gate between Yin and Yang opened, and ghostly blue flames lit up one after another on both sides of the road. Under each flame, a masked person, completely covered from head to toe, slowly appeared. They sat or stood, and with a wave of their hand, various items appeared on the ground in front of them.

Feng An's purpose in coming here was to purchase Heavenly Silkworm Silk, one of the materials for refining puppet silk. He found the seller easily and bought all the stock without much haggling.

After paying, he was about to get up and leave when the seller looked around and suddenly reached out and grabbed him.

Feng An frowned slightly, not understanding his meaning.

The seller lowered the brim of his hat and beckoned him with his finger.

Feng An was puzzled, but still leaned in to listen.

“You come to buy silkworm silk once a month. Last time you even smelled of Seven Poisons Water. These two materials can only be used to make one thing... Although I have never met you, I have already guessed that you must be someone who practices puppetry.”

Feng An's face, hidden behind the mask, suddenly darkened, and his hand, hidden under his sleeve, silently reached for his weapon.

The seller glanced down and gently pressed down on his hand.

"Don't be nervous. I am from the Yin-Yang realm. I know even bigger secrets, and I will not reveal your affairs to anyone."

Feng An's lips tightened. "What do you want?"

The seller smiled. "I want you to owe me a favor—you can't refuse when I need your help. Of course, I won't let you suffer for nothing. As a gift, I'll give you a piece of news."

News? Feng An narrowed her eyes, loosened her grip on the weapon, but still looked at him warily.

The seller lowered his voice even further.

“A few days ago, one of my guests told me in casual conversation that someone has been frequently coming to the Yin-Yang Realm recently, spending a lot of money to inquire about a Crow Clan puppeteer named Feng An.”

Upon hearing this, Feng An's pupils suddenly contracted.