MTL - City: From Inheriting a Courtyard To a Giant - Chapter 648

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

Damien reveals an ugly truth.His sister and only family, Ahara, leaves the house every midnight whilst he's asleep—a time that he soon discovers is when man-eating beasts named Rouges start hunting for prey.Unable to question her directly, he decides to investigate her and quickly figures that Ahara isn't human but rather, a vampire hero who saves them from beings like herself coming from a world she calls Gibbous—a place where entities like vampires, wizards, and beast shifters alike reside. What’s more, he also learns that the real reason behind his parents' death was the leader of the Rogues, who's rumored to have escaped after Damien’s father almost killed him.A series of fateful events lead to Damien’s long-lost power reawakening in him, and he finds himself with no choice but to return to Gibbous, a strange world where power means survival, and weakness leads to death. As such, Damien enrolls in an academy to train his newfound abilities with one thing in mind...Becoming more powerful.However, he soon discovers that the path to power is one filled with troubles and pain, and he isn’t alone in this lust for more at the academy. It’s a bloody competition against time and formidable opponents, and only those willing to sacrifice their comfort are the ones who can attain it.With a deadly foe lurking in the shadows somewhere and a strong desire to protect his sister, Damein has no choice but to fight.The only way is up, and he is going to be standing at the top of them all, ready to counter any enemy.

Liola—the best assassin in his world—has vowed to kill no more. He was being chased by an assassination organization when he accidentally dropped into a parallel universe: through a dimensional gate and into poor teenager Kaiser’s apartment. Instead of going to the government shelter for lost dimensional travelers, Liola and Kaiser wind up going to school together.

Liola has been trying his best to live the life of an ordinary person, but after certain things happen one after the other, he begins to realize that being an ordinary person could be harder than being an assassin.