Mou Zenbu Ore Hitori de Iinja Nai Ka?

In a world where extraordinary powers called ” Beneïsons ” govern everything; only a boy named Kleis was granted the gift of the ” Seint Graal “, a power whose use he could not even understand.
Despite this, he did not lose heart and formed a party with his childhood friend Hinoka, who possessed the beneïson of the ” Seint de l’Espee “, to carry out guild missions. However, due to a minor misunderstanding and betrayal, his mind and body were shattered.
At the same time, Kleis’ beneïson revealed its true potential. The ” Seint Graal ” was the pinnacle of power, capable of granting any beneïson in existence to himself or others.
Having lost everything, yet now holding the power to gain everything, what will he choose? The end of the world or something else?