10 nen goshi no HikiNiito o Yamete Gaishutsushitara Jitaku goto Isekai ni Ten'ishiteta - Chapter 3, Part 5 Yuuji’s, Sending Email to His Imouto, Sakura

Transmigrated-into-another-world-three-good-citizen Gu Xizhou, in order to survive, became a demonic cultivator. No matter how bad or evil, he adapted.

But then…but then he transmigrated back.

The returned Gu Xizhou was very angry. The student that offered his body in order to resurrect him had used a formation that was purposed for summoning evil spirits. He, Gu Xizhou, prior to transmigration was a law-abiding citizen that upheld core socialist values, a three good citizen representative. So how come after transmigrating and coming back, he had become a heinous malicious spirit?!

In each and every one of the spirit worlds, the ghosts and spirits originally lived a Heaven is first and I am second kind of happy lifestyle, that is until in the unlimited spirit mission worlds, inexplicably and out of nowhere came a demonic cultivator.

The ghost and spirits: QAQ

- Description from Novelupdates

There is a kind of person in the world who is indifferent, cool, arrogant, and especially a bit petty. There is also a kind of person who is lazy, gentle, considerate, and even adeptly flirts with girls. When the male god completed a shocking 360 transformation from the former to the latter, Tang Xia’s first reaction was…is this a fantasy world?

- Description from Novelupdates

What happens when a man gets transported into a foreign world filled with magic?

Evolution, it is the process with which the most fit for survival pass down their winning traits. What if this could be done on one animal, one object, one person, what traits would evolve.

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Humanity has been entered into the grand inter-realm competition for sovereignty of all realms.

Darwin has been granted the gift of evolution