Wangshu

Make your way to Wangshu Inn. Teleport or walk there, then head inside and go up the stairs. After a scene, Xiao will appear and tell you to leave.

Go back downstairs and talk to Verr Goldet, the proprietor of the Inn, who is behind the counter. She explains you need to speak to Xiao when he's in a good mood. To achieve this, speak to the chef for a bowl of Almond Tofu and something you can cook well. Paimon will ask what you think is best; answer with 'Satisfying Salad'.

Head to the chef, who is overlooking the balcony. Tell him it's for Verr Goldet. He'll explain the Inn is haunted, and he can't cook the Almond Tofu until the ghost is dealt with.

Head back inside and go down to the kitchen. A scene will play, and a ghost will run past.

Return to the chef and explain what happened. He still won't go back into the kitchen, so Paimon suggests asking Verr Goldet for help.

Go back to the counter and speak with Verr Goldet. She'll ask you to deal with the ghost. She explains about the Witness Sigil, a calligraphy painting in the inn, and tells you to look at it.

Go up one flight of stairs. The painting is on the wall under the next set of stairs. Interact with it to update the quest.

Head back out to the balcony and jump down. You'll see rocks with parts of a golden sigil on them. Line up the sigils on the three rocks so they join. Move back and face the small rock by the lamp post, then rotate your camera until they match. A ghost will then run off.

Follow the ghost south along the path, over the bridge, and then head southeast. A scene will play, showing a broken-down Ruin Hunter. The ghost will run to it, triggering a fight.

Defeat the Ruin Hunter. Be aware of its Swipe Attack (dodge towards the raised arm), Spinning Swipe Combo (dodge backwards), Charging Lunge (dodge towards it and its left arm), and Aerial Bombardment (dodge in a circular motion or towards the enemy). If it uses Aerial Bombardment, shooting its core twice with a charged strike from an Archer can stun it. Electro and Pyro work well against it.

Tell Smiley Yanxiao (the chef) what happened.

Talk to Xiao.