MTL - Demon King’s Political Marriage - Chapter 48

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.

During the first known year, a magical mountain descended into the world from the realm of the Gods. Carved on this enormous mountain was a message: ‘Heaven Prevails’…

After the Grand Descent, a name that was given to the descending of the mountain, the Three Great Sages made their ways to Mystic Mountain where they learned to harvest what we now call magic, establishing the Mystic Cults and eighty-one sacred shrines to help aid mankind with the cult’s mystic powers against the eternal fight to the death with demons.

- Description from Novelupdates

You thought being reincarnated as an extra-side character was bad? Imagine being thrown into the body of a villain who is disowned by his own family and discarded by the author.

A failed investor from 2017 got drunk and woke up in the 1980s. China is just opening up, and the economy is blooming. There is also the dissolution of the Soviet Union, the bursting of the Dot-com bubble and other financial crisis. He used his knowledge of the future and slowly build up his empire.

- Description from novelupdates

A young man was going about a normal day, and he went back home to his house being empty again, his parents had missed his birthday again.Just like all the other years before, there was nothing special about his 18th birthday it seemed.This however was far from the end, caught by something unexpected at his own house, he perished.It was supposed to be the end, however this only marked a new beginning.Faced with a great trial of will, and Karma, and passing with a score beyond anything else, he was given the Class Omni-Layer, and the Job Omni-Ruler along side a system to manage it all.All this to prepare him for a new world, a world of swords and magic, and classic isekai, but this world was anything except an easy trip.