The Fake Madam Disappeared - Chapter 4Vol. 1 -

A human from Earth is thrust into the [Hunter x Hunter] world, becoming the Zoldyck family’s defiant, red-eyed prodigy. They call me a genius and the rightful heir, but I say that’s Killua’s burden to bear.Armed with crimson eyes, and a subtle yet powerful system, I’ll rewrite destiny, upend the world, and embrace the chaos with a wicked grin.

Li Xiao Yao left S.W.A.T to become an ordinary security guard. While working, he happened to enter the VIP room and found Lin Wang Er still in the middle of changing. As revenge, she took him on a ride and kicked him out of the car.

After hours of walking, Li Xiao Yao finally managed to get back home just to be kicked out of the house. He then got an offer from his previous supervisor to become the bodyguard of the Tian Xi group CEO’s daughter both in game and in reality. But unknown to Li Xiao Yao the girl was actually…

- 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?