Dongfang Qingcang telling Orchid he only pretended to love her because of the heart curse
And Orchid being like, "You've told me that before, think up some better lies"
And then she never does believe that he doesn't love her, which I loved because she does have a lot of proof that he does. It was a nice trope subversion. But also, he's not really lying? There is a very blurry line of when he stopped being nice to her just to fix the destiny book/because he didn't enjoy feeling her sad feelings/because her dying would kill him and when he actually liked her.
The ambiguity of the whole thing is really interesting. And then when he's trying to make her fall in love with him again, he's doing the things he did at the beginning with selfish motivations but this time genuinely out of love. It makes a nice full circle redemption arc.