I Saved the World by Standing in the Middle and Connecting Both Sides

[Not a strong female lead] [Cliched] [Redemption] [Multiple unrequited crushes] [A touch of dark obsession] Ji Lan transmigrates, and the System tells her that completing missions will earn her 1 billion for retirement. Using the System's golden finger, she disguises herself as a spider from the start, on the human side. When a monster with a face covered in sores and tears starts chasing her, Ji Lan is lucky enough to unlock livestream comments.

"Your grandpa's underpants are my meal": May the whole family stay safe and untouched.

"Got beaten up by Third Brother": The whole family stays untouched.

"Wai bi ba bu": The streamer is... on... on... on on on...

After Ji Lan manages to survive by keeping a low profile:

"Stealing your perfect meal": 666, she's got cheats.

"Sad Appa Ci": Is it luck, or luck?

On the monster side, Ji Lan survives by pretending to be family. A spider brings her home and raises her as its young, but she runs away. After turning into a mermaid, she blows up the merfolk's toilet, leaving their whole race in deep shit. When she becomes the billion-and-second child of the cockroach leader, she turns into the cockroach kids' boss. And so Ji Lan bounces back and forth between the two sides, playing both ends: I'm a monster, and I invade human territory. I'm a human, and I wipe out all the monsters.