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After defeating the fallen god-king in divine war, Ziel Grisel (Ken Nijisaki) is cursed by his opponent and loses all his emotions. Ken feels the emptiness in his life and decides to create reincarnation magic by using his innate ability to dispel the curse.
Nine hundred years have passed, and Ken has been successfully reincarnated. Unfortunately, the curse cannot be removed, and Ken is forced to live in that era without his emotions. After learning that fact, Ken is determined to live a quiet and peaceful life as... a butler?

Invincible Colorless Butler

"Aaaaaaaaaaaahhhhhhhhhhhhh!" Kalya and the girls roared as they felt the unbearable pain after Ziel doubled the amount of origin power he injected into their bodies. Some of them cried because the pain was beyond their body's tolerance. If it weren't for their willpower, the girls would have already been knocked unconscious.

Ziel knew that forcibly changing the energy source would cause an overwhelming backlash. The human body will automatically reject foreign energy sources suddenly injected and flow within their mana channels.

He felt his heart ache when he saw their condition, but he had no choice. Ziel had to increase the power of the girls as much as possible, and he didn't have much time before the primeval gods came to the Clorius continent. So he decided to use the most effective and fast method even though it was painful.

Chapter 8