Rebel Heart

Sophia Bennett was an office worker until she woke up in another world as the wife of Prince Alexander, with the household already preparing to bury her alive alongside the dead. She kills an imperial envoy with a sword to stay alive, which leaves the prince no way back and forces him into open rebellion. He is loyal and completely besotted with her, and she has strategy and military sense, so she plans the campaign and he wins the empire with it. Once the country is settled the promises he made stop meaning anything. He takes the throne and immediately begins to suspect her, weighing whether to shut her away in the palace or be rid of her altogether. When poisoned wine is set in front of her a second time, Sophia laughs and overturns the table. She built this throne and considers herself entitled to end it. The adviser act goes, and what is under it is harder than anything he prepared for.