The supporting character's harem is very normal - Chapter 377 Lathel will be my student

Jiang Xiaoman was bound to a system when she was three years old. The system told her that she was the lost daughter of a wealthy family assigned to play the cannon fodder in this script. The fake daughter that her parents adopted was the heroine of the story. 

Jiang Xiaoman blinked her eyes and asked, “What is a cannon fodder?” 　 

System: “You all live in a book, and everyone is assigned their role. From now on, you should keep on blackening and be a bad child. Do you see that little boy? He has a bigger role than you, in the future, he will become the big bad villain. Why don’t you bully him now, and show him up real good!” 

The naïve Jiang Xiaoman picked a handful of colorful flowers and stuffed them into his hands. “I’m showing you something really good!” 

System: “…”

Darling, you got it all wrong! Not showing him something good that way!

The little boy: “I don’t need friends, I don’t need company. I’m just a burden that no one wants. It’s my destiny to be abandoned.” 

Jiang Xiaoman: “That’s wrong. Everyone’s existences have meaning. System said you are especially important, even more important than me. You’ll be a really really useful person in the future!” 

System: “…??”

Did it say that?? 

Later on, the system stopped giving Jiang Xiaoman any tasks. Jiang Xiaoman was very sorry and said, “Mr. System, why won’t you play with me anymore?” 

System: “… just try to grow up first and learn to understand every word! You’re killing me!!” 

Jiang Xiaoman worked hard to blacken (not really) under the system’s supervision until she was reunited with her wealthy parents. She scratched her little head and asked, “Mr. System, what about the task? Didn’t you say that we should fight over the family’s wealth?” 

System: “What kind of wealth do you still want to fight over? You already have more money than your wealthy parents!”

A chance to change, to challenge destiny, making dreams a reality, and live a legend! A regular man gains a system that allows him to turn into a fish!

- Description from Novelupdates

An incredibly athletic older brother, Tenryu Taiga. A programming genius girl, Tenryu Fuyuki. The two siblings separated for eight years ended up living under one roof again after facing the problem – a lack of funds for living expenses.

Fuyuki proposes a way to earn money, a core system deeply involved in people’s daily lives, a game that awards you money as a prize for defeating malicious bugs in cyber world, the 《Aries》structure. Taiga after becoming a warrior in the game relying on his inborn senses, is puzzled by the unfamiliar sensation.

One day Saionji Rui, Fuyuki’s best friend appears and is attacked by a mysterious bug― “I’ll be waiting, my prince.”. Hybrid fantasy battle of cheating siblings begins here!

[Mission: Occupy the space, secure your part, and survive until the end.]

After a disagreement with the author, Lee Hee-ro transmigrated to the world of his favourite shounen manga, Adventure King!

But what’s this, characters have to work hard for their survival?

If you’re a two-bit villain, you get defeated by the protagonist from the get-go?

If you’re the strongest on the current map, you get hammered down by a newcomer to show off their strength?

If you aren’t popular with the fanbase, your character gets deleted?!

In a world of endless fights, a crazy sprint to survive just the next chapter begins!