MTL - Rebirth Starts From 2006 - Chapter 857 see the same

Ren Zhouyuan, who loves to study Chinese culture since childhood, has never imagined that his own life would one day be subverted by a foreigner.

Not only do these foreign devils not love the Chinese, but they also scoff at him, looking at his eyes like watching a fool.

After getting drunk, Ren Zhouyuan is for no reason pregnant with a ball, and actually gave birth to a child as a man. This kid is blonde; almost do not have to verify who he is from the “handwriting.”

Ren Zhouyuan does not want to make that arrogant foreigner part of his life, but after fate tied them tightly together again, he found that there was a big difference between this man and the arrogant fighting nationality he imagined.

Leonid: Honey, what does ” Jijiwai Wai*” mean?
Ren Zhouyuan: Refers to people like you
Leonid: But I’m not chirping ah …

- Description from Novelupdates

The story is about a a hitman, Who dies because of his own recklessness and transmigrates into a game he used to play after his retirement as a hitman.I'm not gonna spoil any further, but i might answer few of your questions.Is MC overpowered?Nope, he'll become strong over time and all battle he'll fight will be because of his effort and techniques.Is there magic and adventure?Yes! It have both magic like normal isekai with adventure and fighting with monsters and many other things. There are other important things like “Essence Stone” But let's talk about it in the chapters.There will be harem?Not really, He will be in contact with many beautiful female and males but one waifu but i haven't decided yet.All i can say is, give it a try, I'll try my best to make it worth your time.

I met the male lead in prison.

To save a doomed fantasy world, I killed the main characters, then destroyed the game world, and fell into another timeline as the academy's top seat and rival to the protagonist.Now, I'm trying to save the world and steer it towards a better ending…But I'm the final boss.