The Apothecary Diaries 11 by Nekokurage
The continued adventures of Maomao. Spoilers ahead for the earlier ones.
As in, it opens continuing the cliffhanger. Maomao did, indeed, figure out the secret of the puzzle set to the Emperor. Bad jokes about the Emperor's taking her as a consort. The Emperor's family history features heavily in the rest of the story, with a mystery revealing many of the darker elements.