[A Few Notes: 1. The heroine is an emotionally steady, easygoing little cat. 2. The hero is more of a background character. 3. Chinese-style fantasy with only a light Western fantasy flavor.]
After completing missions in ten worlds, the laid-back little cat Xivia can finally retire.
When the System asks what she wants as retirement benefits, she makes a wish: a house, land, freedom, and all the memories from her ten lifetimes preserved.
System: OK.
So she is sent to an alternate Western magical world, where she becomes an obscure princess dispatched to a barren territory.
Xivia: ...
None of the ten worlds she'd visited before had been Western fantasy! Sure, her name sounds Western, but she doesn't know the first thing about that kind of world!!!
Well, she's here now, so Xivia can only accept reality, keep living as a human, and work hard to cultivate the vast, barren territory, unlocking new plots of land as she goes.
The territory is huge, but there's not quite enough land for her to farm. No problem. She'll happily claim all the surrounding uncultivated land for herself, until everywhere she looks belongs to her.
Also, her castle seems to have a little problem.
Late at night, Xivia, transformed back into a calico cat, prowls around the castle on patrol. She gazes at the enormous seal hidden in the darkness, hears faint, enticing whispers in the air, and falls into deep thought.
Xivia extends a paw.
Xivia adds eighteen more layers of seals.
Xivia leaves, satisfied.
Don't even think about tempting the great Cat Emperor!
After spending hundreds of years in darkness, the Demon King finally gets a chance to escape his seal. A human princess with an exceptionally radiant soul has arrived in his land.
So he tempts the princess to break the seal. Failure: she only strengthened it.
Then he tempts the princess to attack the neighboring territory in hopes of starting a war. Failure: they're too poor to afford one.
He switches tactics and tries to seduce the princess. Failure again: in her heart, he's not even as important as a crop of wheat or a litter of piglets.
Demon King: ...
Why is this human so difficult to deal with?!
He glumly continues watching the princess, looking for a chance to trip her up. But one day, he unexpectedly sees the Crown of the Undead and the Goddess's Crown floating above her head.
Demon King: …
Fine. There's no hope.
Theme: Keep your feet on the ground and work hard to build a better life.