Princess of the Void - 1.14. Groom’s Code

After dying from betrayal, Thomas reincarnates as Jolthar Kaelzhar, the neglected son of a powerful clan, just after his brothers kill him. With Jolthar's memories and the blessing of Qalena, Thomas vows to rise from his lowly position and claim power in his new life.

I turned my assassin into my maid with the power of money! Money is all-powerful!

It was a world full of swords and magic; Lawrend was the son of the wealthiest merchant in town. Since the age of 7, he had been having dreams. A dream about a past life in a modern civilization where monsters are nonexistent, and humans dominate the world. Lawrend saw Iron birds, Magical bricks that display moving paintings, Thunder wielding, and many more.

There was a scene in one of the dreams that made Lawrend’s heart beat fast. A row of a dozen maids bowing in front of him. Each dressed in a french maid outfit.

Something awakened inside Lawrend when he had that dream. A fervent desire to have his very own Maid Harem!

What the hell? That menace who bullied me since I was six years old, actually became a pretty girl after three years of living apart? And she even ran to our agreed duel location to confess to me, hoping that I can become her boyfriend?!

This is a plot against me! There’s definitely an enormous conspiracy behind this! I won’t be fooled by you! Even if you tear up and act all pitiful, I will still disregard you and humiliate you, until you’ve have completely paid back all my childhood grievances!

What’cha lookin’at? There are very reasonable grounds for bullying a girl!

- Description from Novelupdates

In a future timeline, the earth was visited by a species known as the Slarkovs.
Having lost their home planet and in search of a new one, earth was the next habitable planet for them.

Humans and Slarkovs made a deal with each other in return for the Slarkovs living on earth.
The Slarkovs traded their technology and knowledge for a new home.
They were similar to humans except for some of them who had slight differences so fitting into the society wasn't a problem.
Over the years Slarkovs and humans began to mate with one another and reproduce offsprings.
This in turn created a new species known as the mixed-blood.
Centuries later mixedbloods could tap into their bloodline and perform unimaginable feats.

Gustav born into an age where bloodline determines everything, struggles to fit with a useless bloodline.
His bloodline only grants him the ability to change his hair color, destroying his hopes and dreams for a great future.
His fate is turned around when an unexpected situation leads to him finding a system that grants him the power to unlock and upgrade bloodlines by completing quests but he's baffled by two quests with a five-year deadline. Success will grant him unimaginable rewards...
But only one thing awaits him if he fails... Death!

Follow Gustav on his interesting journey filled with unprecedented adventures, danger and death, maybe?