They are the smutty parts that were censored, the artist uploaded It in Twitter some time ago, so maybe they'll upload here the Incense burner extra too.
This is after the guanyin temple scene(it's the uncensored version, it's from the novel), when Wangxian elope and do it at the bushes(if I'm not mistaken).
The artist of this smut scene is the official artist of the manhua(they just can't add the explicit version, because of china's censorship).
Oh c’mon give us plot!!!