The supporting character's harem is very normal - Chapter 465 Friendly Points

Jiang Pengji got something called the Court Intrigue Stream System.
System: “Your goal is to become the most prestigious woman in the kingdom (the Queen)!”
Jiang Pengji: “Okay, System. No problem!”
Years later, she met the target by becoming the most prestigious woman (the Empress).
Jiang Pengji: “Well done, no?”

- Description from Novelupdates

Content Warning: R-18, Smut, Cruel MC[Ding! You've acquired the Heroine Stealing System!][Your first task is to steal the daughter of the Eastern Kingdom's king!][Your Fate Value has increased by 10!][You've slept with the hero's mother, your Fate Value has increased by 15!][The hero has developed animosity towards you. Current Hatred Level: 5 stars][The king's wife is charmed by your looks.]After being transported from his own world, the protagonist wakes up as Vritra, the son of Demon King Rohan from the Hell Continent.Since he's from another world, he doesn't have any Fate Value in this new world of swords and magic.To survive, he has to act like a villain, stealing the affection of every hero's heroine and sleeping with them.This will boost his Fate Value and help him stay alive in a world filled with wars and political conflicts!

Everyone said Su Xiaofeng from Lihua Village was lucky, despite having two kids to drag around, she still married a big shot from the Imperial Capital, making everyone green with envy.But the truth was this:In the 21st century, Su Xiaofeng, a leftover woman who started her own business, died unexpectedly while pregnant and was reborn into the body of a village girl from the 1990s.Right after arriving, she discovered the shocking news that she was pregnant.Touching her chin and then excitedly patting her stomach, Su Xiaofeng said, “It's like finding what you've been searching for without any effort at all.”To ensure that after the baby's birth, she could do whatever she wanted, Su Xiaofeng rolled up her sleeves and got to work, and by accident, she obtained a Spiritual Mirror, renowned for its wealth and beauty.From then on, she went further and further down the path of stepping over Lianhua, tearing apart local thugs, torturing her unkind mother, and beating up big shots... wait, no, on the path to getting rich.Only, her twins were beginning to look more and more like a certain big shot from the Imperial Capital.This story is fictional; rigorists beware!

From the age of 7, Qiao Qiao realised that her family wasn’t quite the same as her friends’ families.

Her father, dressed in all white, said, “Our girl should learn to cultivate immortality with me!”

Her mother, dressed in battle armor, said, “Our girl should train her body to protect herself!”

When discussing it, they decided to solve it with a duel outside.

Her brother secretly asked, “Qiao Qiao, do you want to be in the entertainment industry with me?”

Then, her brother was kicked out of the house by her parents. She prayed that he was okay out there. 

Qiao Qiao sighed. She was really worried about this family.

She silently collected mech building materials. There was no other way, if she learned how to use mechs, she would be able to get a good job. Unfortunately, her unreliable parents didn’t understand.

It seems like the burden of supporting this family was handed over to her.

- Description from Novelupdates