The supporting character's harem is very normal - Chapter 461 Karol Magic Academy.

The world of Wageah was vast. It was filled with ancient magic, fallen gods, legendary mages, and exciting adventures.Earthlings summoned there gained godlike power.Zeus, Odin, Count Dracula, the Monkey King. All of them were humans who returned from Wageah and became legends on Earth.But my class and I, who were summoned to Wageah?We were enslaved.We were used, discarded, and left to die.But fate gave me another chance.I woke up as a newborn on Earth with all my memories intact. And soon after…[Awakening Supreme God's Treasure: Shadow][System Boot Successful]I gained strongest weapon in existence. [Shadow]. The treasure of the Supreme God.This time, I’ll grow stronger from the cradle. And when I return to Wageah—I won’t be a slave.I’ll be the shadow that devours the gods.

An advertising director is reborn in 1988 Hollywood as an eighteen-year-old blond-haired westerner named Eric Williams.

From then on, he starts writing movie scripts and television songs, becomes skilled in directing every kind of film, wins over all kinds of female celebrities, and takes the road to become a Hollywood legend.

- Description from Novelupdates

“One Generation Immortal Venerable” Luo Chen was attacked and reborn and returned to Earth.

He is an ordinary person, facing the contempt of his girlfriend, the ridicule of his rivals, the miserable life of his parents, and the threats and provocations of the rich and young.

He vowed to change the injustice of fate, stand on the pinnacle of this world, and tell everyone that Luo Chen had been here.

- Description from MTL

A certain girl aspiring to be an adventurer was invited to join the Hero’s Party by chance and became their apprentice. However, she was not actually treated as a real apprentice, and was subjected to physical violence and verbal ab*se every day.In the end, she was told that she had no talent and was about to be expelled from the party.However, the hero promised the girl that if she could stay in the Demon Forest for a week, her expulsion would be revoked. Unaware of the fact that she had been tricked, the girl was abandoned in the forest without even a weapon to defend herself.But the Hero’s Party had no idea that the girl had been observing every battle they had faced. Nobody knew of the girl’s talent.A talent, for which even the word “genius” would be too modest to describe, would allow her to reach the realm of excellence.The girl who was able to escape the forest soon registered herself as an adventurer, and in no time, she overtook the fierce fighters one after another.This was a tale of the rapid growth of a girl with the strongest physical prowess.A talented monster doesn’t need to be taught – someone once stated.