The World Darkens

He stands over the corpse of the demon lord, looking cool as ever despite the gore and ichor from not just the demon lord but also the top lieutenants he slew to get to this moment.

The rank and file soldiers cheer, the centuries long war with demon kin is over, the hero did it the world is saved.

His weapons and armor dissolve into sparkles of light before resolving back into the women who had stood by his side and lent him their strength through this journey.

"What now Sato?" asks a blonde girl in a highly fetishized clerical robes.

Sato, the hero from the other world, savior, slayer of demon kind's most lethal warriors, smiles like a hungry wolf:

"Now we take what we are owed."

When the hero demands the throne as compensation for his work in slaying the demon lord the king laughs and his nobles join nervously in.

After five years of solving every problem with powers grown to fight demons, the Hero has no problem slicing the king down where he sits.

By the end of the year even the villages most ravaged by demons wish for the demon lord back.

By the end of a decade, the land prays for a miracle.