The Radiant Emperor #2 He Who Drowned the World (original) Shelley Parker-Chan

Zhu Yuanzhang, the Radiant King, is riding high after her victory that tore southern China from its Mongol masters. Now she burns with a new desire: to seize the throne and crown herself emperor.

But Zhu isn’t the only one with imperial ambitions. Her neighbor in the south, the courtesan Madam Zhang, wants the throne for her husband―and she’s strong enough to wipe Zhu off the map. To stay in the game, Zhu will have to gamble everything on a risky alliance with an old enemy: the talented but unstable eunuch general Ouyang, who has already sacrificed everything for a chance at revenge on his father’s killer, the Great Khan.