MTL - Rebirth Turn of the Century - Chapter 756 One of the achievements, SIRI

She is the slow-witted idiot of the Prime Minister’s Residence. Everyone bullies her. He is the most respected and unfeeling Prince, with frightening ability and absolute envy! Together, they are conferred an imperial edict of marriage.

She acts stupid and tries to decline in every way possible while he despotically escorts her into the wedding…… everyone ridicules the match, but no one knows that the “idiot” has transformed from a loser into a talent.

After the marriage, when they encounter the Empress Dowager examining the room, they act in concert with each other and pretend to be two mandarin ducks deeply in love. Afterwards, she laughs, “The performance has ended. Your highness, please return.”

He laughs softly, “Since you’ve got onto this Prince’s bed, don’t even think of getting off.”

- 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?

She is one of the best thieves that the world has seen in the 24th century. However, not even in her wildest dreams had she imagine that she’d be reincarnated as a good-for-nothing orphaned Seventh Miss of the Vermilion Bird Family. She finds herself stuck in a family that mistreats her, as well as an unfamiliar place with no support system.

Kai was a 17-year-old dropout. A NEET. A background character in real life with nothing to his name but bitterness, novels, and guilt. After his parents died, he gave up on the world. People were fake. Dreams were pointless. And that one novel he kept reading? He hated it especially the main character, June. Perfect, noble, always standing tall. Everything Kai wasn’t.Then, one night, a voice asked: “What if you did meet June?”He said yes, half-asleep and half-mocking.Now he’s trapped in the novel. Isikeid. But he’s not June. He’s not a hero. He’s not even in the main cast.He’s an extra in the background of a world he knows too well and he’s had enough of watching things play out the same way. This time, he’s going to change everything. Whether the world likes it or not.