Shift! The Side-Character Heroine - Chapter 6

Lin Chen was persecuted by his childhood sweetheart and accidentally obtained an ancient legacy. From then on, he embarked on a path against the heavens!“I am a sovereign! Those who insult me will be killed, those who obstruct me will die!”

800 years ago, 3000 dimensional gates opened across the entire world. In that moment, it was as if 3000 different colored eyes opened across the world as hordes of monsters swarmed out of these gates like tears.

Some could destroy city walls with one strike; They had bodies the size of a giant and fed on humans

Some latched onto humans, absorbing their bodies’ nutrients and enslaving humans

Some infiltrated the humans’ cities, disguising themselves as normal human beings while feeding upon human blood to sustain themselves.

In a night, the Human race fell to the bottom of the food chain.

The world had turned into a paradise for monsters…

Humanity had finally ended the war with the Demon Race and sealed them away, forever.However, they now have to face the treat of the Shadow World, an equally dangerous threat to their civilisation under the rule of the Emperor!Facing only misfortune from a young age, Nikolaus Reinhardt never expected anything good to happen to him.But his world completely changed when he awakened as an Ascendant, and accidentally summoned a member of the Demon Race in his house.Just because he messed around with a god damn book!

In the current era, people are either normal or are with ‘special abilities’. Cases related to the latter are managed by the “National Anomaly Prevention and Control and Special Species Management Office”.
Qi Zheng Emperor Sheng Lingyuan was reawakened a thousand years later after he jumped off the fiery Red Lake. Xuan Ji, a newly transferred staff to the Reparations Division of the Deviant Control Office, finds himself having to clean up the mess of a revived tyrannical monarch. The two seemed to share something from the past, but unbeknownst to them, a big conspiracy is stirring right underneath their noses that could destroy the balance of the world.

- Description from Novelupdates