Our story begins with an encounter:
a creature bestows magic that makes the "impossible" possible.

Mine D. Raul is a "keiyakuju", a beast that makes contracts with humans.
In doing so it gives the contractee unlimited magical freedom.

The power to make the impossible possible.
That's true magic.
If you wielded it... what would you do?

Young boys with good intentions make their contracts.
To bring humanity together.
To defeat evil.
Compassionate shonens.

But compassion, virtue, dreams, hopes...
They are all corruptible.

[From DLsite English]