Roaring Heroes Battle the Overlord (Ainz)

It borrows the world and characters from the anime "Overlord," but the plot is entirely original.
This is not a light and pleasant story about a great, glorious, and righteous hero challenging an evil Overlord.
On the contrary, it depicts a female character with significant flaws, fighting the toughest and most brutal battles against the Overlord in a dark world, and growing through these conflicts.
There are two main characters:
One, a quirky yet powerful girl.
The other, a mature and steady male adventurer, albeit weak.
They embark on a journey to battle the most powerful evil Overlord, Ainz Ooal Gown.
So can they succeed?
Note: There is almost no romance plot.