Hero of Darkness - Chapter 26: The Arrangement

When the average man is suddenly thrown into a video game as an extra, fated to die, they might first think to hide or run away. But not Luka. A man now inhabiting the body, he simply wants to survive - no matter the cost - even if it means he has to kill the main character!

Nate, a transmigrator from Earth, arrived in the anime world of Fairy Tail!He acquired a magic called “Internet!” He developed it and got everyone hooked!You can livestream, chat, and even... hmm? Find girls to date!Sasuga Nate-san, Internet Magic is the best!

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

Xiang Ye (Ah Ye) and Charles have the fated arrangement of master and servant. In the depths of darkness, Ah Ye scooped up Charles – a vampire butler. Possessing a fervid passion for service, Charles single-mindedly attends to the secretive young master Ah Ye – regardless of his ferocious appetite, abhorrent taste in clothing, and relationship failings – for the master is always right.

On the other hand, in the chaotic era of scientifically enhanced humans, powerful heroes become the protectors of normal citizens, going where evil needs subduing. This young master may be secretive, but he is our hero.