The Cannon Fodder Supporting Actress Refuses to Follow the Plot [Period]

After spending ten years in the apocalypse, Li Yu finally confronted her enemy and perished alongside her scumbag father and his family. She never imagined that she would survive, only to transmigrate into a story set in the 1970s. She even became Li Yu, a cannon-fodder supporting female character who barely appeared in the book. Li Yu never expected that not only would she get revenge, she would also reclaim the storage space that should have been hers all along. And the things inside seem perfect for this era!

But before she can start living life on her own terms, she has to deal with the awful people around her on behalf of the original owner:

Dear old dad, you've been using your position to pass off inferior goods as top quality for years. This needs to be reported.

Dear old mom, you've got an entire operation going, from production to sales, and you're even trafficking people out of the province. I have to put justice before family.

Dear big sister, you need to quit stealing things, or I'll break your third hand.

Dear little brother, you'll grow up to be rotten to the core. Do you really need to grow up?

And you, the birth father who sold his own daughter but is raising someone else's child, watch out. Your comeuppance is coming!

Original male and female leads: We went through test after test to be together. Where are the tests now? What happened to them?

Li Yu, who goes crazy and spares no one: I went too far. Someone's got their eye on me!

Male lead: She's richer than me, and her temper's even worse than mine? This is going to be a problem...

Theme: Prosperity, democracy, and civilization