After losing a bet with God, I was forced to go to another world and play the villainous Demon King.
But then Livia discovered that the script God had given her was an 18+ one, and an 18+ one with gore, at that.
To avoid becoming the final defeated CG in the script, Livia decides to kill the hero before he even makes it to the beginner's village.
First, she sends a vampire to seduce him. Failure.
Then she sends the elite forces of the Demon King's Army to face him head-on. Failure.
This is a real case of losing both herself and her troops. To keep anyone from discovering that she's the final boss, Livia has no choice but to pretend to be an innocent little girl.
Behind the scenes, she follows the script and steals the heroines away from the protagonist one by one, tricking them into joining the villains before he even meets them!