The supporting character's harem is very normal - Chapter 214 Rules in the Novel

Have you ever thought that the state of the world as it presently is, could revert to the laws of the ancients? When a series of strange incidents beginning with the disappearance of his friend led Luo Yuan to question the possibility of an apocalypse, he becomes embroiled in the midst of a global-scale chaos.

Evolution has turned the flora and fauna of the vast and bountiful Earth into something that had never been seen before. Coincidentally, the all-dominating Homo sapiens have ended up at the bottom of the food chain. From mystery to crisis, will Luo Yuan discover a means of saving humanity by racing to the top of the food chain? Or will he strive in accordance with the law of the jungle? It is the dawn of an age of the survival of the fittest.

- Description from Novelupdates

The young man Ye Tian obtains the ability to copy the talents of others and now fights against the heavens to change his fate. He struggles to survive and protect his sister from the apocalypse of the alien beast invasion. In order to become stronger, he begins to explore the unknown world and gradually reveals the secret behind the invasion of the alien dimensions…

Gawain is dead and was transmigrated, but there was a slight problem during the process.
After floating for more than a hundred thousand years on a different continent, he felt that he might need a body to become a complete transmigrator, but he did not expect that…

- Description from Novelupdates

Caelith doesn't want too much in life, a clean home, a happy mother, and maybe a girlfriend. Raised in the Stormont manner, one of the highest ranking noble household in the kingdom, he grew up a bastard, mistreated and abused by the main lineage.At the tender age of sixteen nobles undergo a divine ceremony, receiving the opportunity to be blessed by the gods however he receives Nothing.Caelith struggles in this world but at the end of the day, He is Nobody, and he has Nothing.