Space and Rebirth: The Favored Genius Doctor and Businesswoman - Chapter 26 – Adorable Space Bug (空间萌虫)

A reader has been watching Hanyu for so many years and can’t help but revolt!

This is a Korean entertainment in my imagination, not a stallion, not a red palace. Korean entertainment that is as close to real life as possible

- Description from novelbuddy

Ye Song, who once lived in a technologically-advanced world, died and reincarnated into a noble teenager’s body in another world.

A fantasy world filled with magic!

A series of events filled with tragedy, action, etc. began to unfold one after the other when he fatefully encountered one of the most guarded secrets of this world, obtaining the legendary power of Wizards.

Watch how he reaches unreachable heights as a powerful Wizard in this new world.

- Description from Novelupdates

Matthew, a 25-year-old otaku, never imagined his obsession with fantasy worlds would turn into reality—until a fatal gas leak ended his life and transported him to another world.But this wasn’t the second chance he hoped for. Born as the illegitimate son of an affair, his very existence was a stain on his family’s honor, and his father relentlessly sought to kill him.Yet Matthew, now Claude, survived, again and again, driven by an unyielding will to live.Until one day he discovered his power darkness. Feared and reviled in this world, dark mages were hunted and burned alive.Knowing his gift could become his downfall, he trained in secret under Theo, his true father.When he turned sixteen, he, his mother, Dalia, and Theo planned their escape from the small town.But their attempt was thwarted by knights and clerics from the Promised Land.Though he narrowly escaped with his life, the cost was high—his family’s safety shattered.Wounded and desperate, Matthew fled to the fabled Elysian Plains, the last hope for those like him.Just as he reached the border of the Elysian Plains at eighteen, an ambush left both him and his mother gravely injured.Collapsing on the sacred ground, he heard a voice echo in his mind:[Welcome to the Elysium of Darkness System, Lord of Calamity.][Your first quest is available!][Increase the number of dwellers in the Elysium using your seeds and blood! Spread your legacy by making demons and witches bear your children!]

Another entry in what you can call the Proto Harem Series: the books written before the Harem Series that take place in the same world.

It’s about a swordswoman whose student is captured, so she goes to rescue her.