Mahouka Koukou no Rettousei - Chapter 2Volume 4 -

Liu Fang, a manager, died suddenly at work due to being too diligent.
She thought that she would turn into a wisp of dust and dissipate after her death, but she never imagined that – the new century, the new underworld, even if she became a soul, she would still be a worker!

Liu Fang has become a newcomer to the underworld Quick transmigration Department. In order to wait for a good reincarnation, she strived to accumulate merit and traveled into one world after another to repair the way of heaven.

- Description from Novelupdates

Rimu Dynasty, Kingdom of chaos. Demons were rampant, and it was difficult for people to live.

Gu Qing’an had not yet had the opportunity to appreciate his beauty upon transmigrating in this world, as he had to face the demon who targeted and devoured humans.

Fortunately, she had a system.

“I, Gu Qingan, have never been weaker than others. System, add it to me.”

……

Many years later, Gu Qing’an, standing on the frozen void, looked at the newly discovered strange world under her feet without any expression.

“Compared to human beings, alien existence is a demon,” she thought to herself.

“Then, are all creatures in this entire world considered demons?”

- Description from Novelupdates

Our protagonist Caam is a man from Earth that was reincarnated into this world as a demon. In order to survive, he spared no effort in avoiding the sparks of battle and without noticing it, he became strong himself.