MTL - I’m Working As a Renter In An Unfinished Building - Chapter 613 we were strayed

A 30-year-old NEET is reincarnated into the body of an otaku that choked to death on instant noodles. As he comes to grips with his new life, he realizes that this world is subtly different from Earth. The denizens of this world are far better looking, and this new world also possesses futuristic technology as well as mysterious Yin Yang masters!

The eldest daughter of the Yan family, Yan Jinyu, who has been missing for 16 years, has been found. She is brought back from an orphanage by her fiancé, the Second Master of the Yin family.

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.

Bai Yang is the youngest son of a rich family, he grew up spoiled and unambitious, and no one expects anything from him. He doesn’t really mind this though, because he’s still able to live a simple and happy life.

One day, however, his older brother got into an accident and is now comatose. Bai Yang’s father now has to consider his youngest son to take over the family business. Unfortunately, for him, Bai Yang is a weak, timid, and cowardly child. How can he ever succeed?!

Wanting to change his son’s personality, his father has Bai Yang transmigrated into the world of Wild Wind, a very famous fantasy novel. Bai Yang’s father hopes the environment of that world will shape his son into a more arrogant and domineering man, as a child of a wealthy family ought to be.

However, due to an error in the Main System, instead of transmigrating as the protagonist, Bai Yang ends up becoming a cannon fodder villain, Xie Zietian, from the Demon Realm! In order to safely and quickly return to his world, Bai Yang has to ensure that the protagonist, Zhou Ying, ascends to the heavens so his transmigration mission will be completed.

In order to sneak into the Human Realm and help Zhou Ying, Bai Yang comes up with a variety of excuses to the Demon King of Everlasting Night, such as…

Bai Yang said in a dignified manner, “Your Majesty, that person might threaten the demon world. I will go to the human world to kill him for you!” (Actually, I went there to meet the protagonist.)

Bai Yang proclaimed his loyalty to the Demon King, “Your Majesty, hang in there. I will go to the human world to find the elixir for you!” (Actually, I went there to save the protagonist.)

Bai Yang said with an attitude of selfless dedication, “Your Majesty, I just want to go to the human world to further your great cause!” (Actually, I went there to see the protagonist.)

The Demon King’s face remained impassive but, in fact, the tips of his ears were red. He was thinking: I can’t believe he loves me so deeply…

Demon King said, “Humph! Seeing how clingy you are, I’ll accept your love. Tell me! Whatever you need, I’ll give it to you!”

Bai Yang: “What the hell…! Your Majesty, I don’t love you.”

Demon King said, “No, you love me.”

The Demon King truly believed Bai Yang and him shared a deep mutual love until he discovered that Bai Yang was having an “affair” with a “wild human” …

- Description from Novelupdates