What do the incense burner stems and the dust stem stems in "The Patriarch of the Demonic Way" refer to?

The story about the incense burner is: After everything calmed down, Wei Wuxian lived in Gusu, and he and Lan Wangji were inseparable. The two of them took naps every day, and the incense burner in Lan Wangji's room was damaged for a long time. Surrounded by the spiritual energy from unknown places in Yun Shen, it turned into a spiritual thing, and the fragrance it exuded brought Wei Wuxian and Lan Wangji to a world of nothingness.

It turns out that the incense burner received the dreams of Wei Wuxian and Lan Wangji into the incense burner, and brought the two people in to see the dream of 16-year-old Lan Wangji. In the library, Wei Wuxian The scene where Lan Wangji is frightened by the erotic pictures was filmed in both anime and TV series.

Bi Chen meme: The original text reads: "Wei Wuxian stared at him with a smile, took Bi Chen in his hand and shook it, lowered his eyes, and kissed Bi Chen gently on the hilt of his sword. After a while, he put out a bright red tongue and licked the sword hilt carefully."