She transmigrates into the fourth daughter of the Su family in the 1970s.
Only three years later does Su Lixia realize she's transmigrated into a period novel.
Transmigration isn't scary, and transmigrating into a book isn't scary. What's scary is transmigrating as a cannon-fodder character.
The eldest sister is cheated out of her money and love by a scumbag, and is eventually driven insane.
The second sister is kidnapped and sold to a mountain village while traveling away for work.
The third sister is a minor supporting character who steals the heroine's fiance, becomes utterly disgraced, and throws herself into a river.
Even ants know to cling to life. Su Lixia isn't going to lie flat and wait to die. She's going to defy fate and change her destiny.
Theme: Work hard to realize your value in life