A man who was a company slave died from shock at the same time as he completed the popular game "Sorcerer Awake".
He is reincarnated as Leon Ornstein, a villainous aristocrat who is supposed to become the "Demon King," the last boss in the game.
And by some chance, he also obtains the power of the secret boss, "The High King".

Q.Do I play as a villain with the power of the two bosses?
A. "Now that the world is at peace, I don't want to be a villain.

Instead of being a villain, he will be a ally of justice, solving various problems with the cheat magic of the last boss and the hidden bosses!
Aim to become the strongest mage, live a slow life, save the world from crisis, and more!?

With his sister, who is a bit of a yandere, and the energetic female protagonist, Leon enjoys his new life..!