Xie Qizhao transmigrates into a book with a System and becomes a cannon-fodder heir in men's clothing, a character who gets just one line in an old-fashioned angst novel. Her main quest is to find out why the story's plot has changed.
Xie Qizhao: Me? This cannon fodder?
System: Ahem, yes, Host. But we have the golden finger of refreshing medicinal herbs!
Xie Qizhao stares silently at the human feces and urine in her hands.
Before she can even start the quest to get close to the protagonist, she's suddenly told that she's engaged to the original story's greatest villain.
Xie Qizhao: My wife is gorgeous, but I'm a mission-driven agent with principles! (Sneaking a glance at the cold and aloof Shen Tangxi.) But, well... a kiss, darling.
Shen Tangxi: I knew I should have killed her from the start.
Ever since childhood, Shen Tangxi has believed that one day the throne in the great hall would be hers. She has worked hard toward that goal, but one day, she is accidentally kidnapped by her enemies. The unlucky heir of the Duke of Dingguo is taken along with her.
Shen Tangxi easily escapes with the unlucky heir, but along the way, he overhears her greatest secret. Before she can silence him, he is taken back to his residence. When the heir wakes up, he claims to have lost his memory and remember nothing.
To keep this liability close, Shen Tangxi binds him to her with an engagement.
Much later, Shen Tangxi ascends the throne. A fearless censor remonstrates in court, begging the empress to hold a selection of consorts and ensure the royal line continues. Before the empress can answer, the General of the Cavalry, Xie Qizhao, leaps forward and hurls the memorial at the censor's head.
Shen Tangxi: It's not my fault. She's just that devoted.
Theme: Women, too, can ascend the throne.