MTL - Age of Evolution: Opening Awakening Tenseiken - Chapter 195

In the middle of a deserted island, a small boy wakes up with two sets of memories: one from his few years of life and the other from a man who lived to adulthood and achieved great things. When he least expected it, a powerful master appeared on the island and took him in as a disciple, revealing a shocking fact: magic exists in that world, and, thanks to it, humanity managed to conquer the galaxy.

“The biggest blessing in my life was meeting you. The greatest misfortune was hurting you.” — Ye FeimoOn the night she finally confessed her feelings, Wen Nuan entered the wrong hotel room—and woke up in the arms of a stranger.Drunk, confused, and heartbroken, she never expected that one night to bind her to the ruthless and enigmatic CEO, Ye Feimo.To find her, he boldly posted a half-naked ad of her across the city. To own her, he made her sign a contract as his substitute lover.She thought it was love. He only saw her as a stand-in.When the woman he truly loved returned, Wen Nuan vanished without a trace.But it was already too late.Ye Feimo finally realized that the only woman he truly loved... was the one he let go.

500 years ago, Chen Xi was devoured by a crack in the void and was transported into a cultivation world.

500 years later, he returned back to Earth after enduring through several hardships and discovered that only 5 years had gone by.

…

In the courtyard, beauty at the side, a candle flame wavering.

A gush of clear wind, half a full moon, the peach tree remains unchanging.

…

Wait, whose kid is this?! Why is she calling me papa? Gazing at the little girl in front of him with skin as pale as jade, Chen Xi froze.

…

　
Returning home from cultivation, starting as a stay-at-home dad.

In this life, not fighting to be a king nor claiming to be a tyrant, only praying to peacefully be a wife-pampering mad devil and a child-protecting daddy!

- 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?