Akame ga Kill: Starting with Dual Kamui - Chapter 2: Esdeath

They took his name, stole his life, and fed on his pain. But they made one mistake—they let him live.Betrayed by his own blood and sold into slavery, Prince Oliver Von Rich lost everything—his title, his freedom, and his future. For years, his captors in the Somaran Empire bled him dry, using his Royal bloodline as fuel for their Aether.But when they sought King Solomon’s Staff—a relic said to grant any wish—Oliver rebelled. Left beaten and dying, his blood soaked the ancient artifact… and awakened it.Dragged back in time to the eve of his kingdom’s fall, Oliver is no longer a helpless prince. With the scars of his past and knowledge of what’s to come, he’ll rewrite fate—even if it means becoming a monster.To destroy the empire that broke him, Oliver must embrace the cursed power of the most vile demon known to man.

Ziel Grisel (Nijisaki ken) succeed defeated the fallen god-king in divine war. But he was cursed by the god and lost all his emotions. Until finally he created the reincarnation magic of his skill to remove the curse.

900 years later it has passed and ken successfully reincarnated. Unfortunately, The curse cannot be eliminated. And ken must be forced to live his life without his emotions. Ken finally Determined to live a quiet and peaceful life in those days as a….Butler?

A fighting genius.

This stands at the forefront of strategy guides to Life (a shitty video game)!