"Well, liquid means... all this oil of earth!" And if it's still out... it's a hell of a score! You can live a lifetime!" (Rei)
Can't believe it! The oil king route suddenly occurs in such a place! The winner is determined! After purifying all this oil to make gas...
"Hey, is this very nice? What is this?" (Niram)
"That's right! For example, it burned, with the heat it could produce electricity, then..." (Rei)
"Burning? Electricity? I don't know, it's faster to do it with magic? Using electric devices..." (Kiki)
"Ah..." (Rei)
Well... in this world all energy is magic. Besides, it's much better for the environment than oil, and the cost can be restored by using magic powers to eat and sleep. There's no other ecological energy like this.
So you don't need oil in this world. There's also a chemical fiber made of Earth oil, but I wonder if it could also be a monster matter. It's a world where no need for oil.