The supporting character's harem is very normal - Chapter 459 You can do it

My handsome, overpowered dad, who only ever cared about me, ate something strange and turned into the Demon King. He used to be the sweetest, most doting father, but now he’s the final boss?! Because of this, my dad is fated to be killed by the male lead, and I’m destined to die lonely while mourning him. At that moment, I returned to the past and realized that this world is actually a game! I couldn’t prevent my dad’s descent into darkness, but no matter what, I must turn him back into his original self. If I succeed, I can get my loving dad back, right? For now, I need to get close to the male lead, who’s destined to kill my father…! So, I became a Holy Knight and even managed to be adopted as the ward of the Pluto Ducal House—the male lead’s family. …The problem is, I’ve become way too strong. As long as I get along with the male lead, my dad might avoid being labeled as the Demon King. “But that’s strange.” “…What is?” “Your lips… they’re heart-shaped.” “W-what? Don’t look at my lips!” At that, the male lead tried to avoid my hand and ended up rolling under the bed. “Ahhh!” “…?” He’s supposed to be the strongest person who’ll one day kill my dad, but for now, the male lead is just too cute.

After accidentally falling, she actually finds herself bound to a Second Female Lead Counter Attacking System!

The low-ranking behemoth, the iron mountain is invincible in the horizontal push, and it is called the king of the backing.

- Description from novelbuddy

At first, when he learned that he was forced to go to many different routine worlds and be reborn into all kinds of cannon fodder, he was against it.

Because villains usually all only have a moment of satisfaction, the endings of cannon fodder are also frequently quite miserable.

But the man who gave him the system told him that this system not only has all types of powerful functions, but he can also break the routine lives of the cannon fodder. If he achieves this satisfactorily for each world, he can even become a god.

He’s already experienced over a thousand reincarnations, but hasn’t yet been a god. Since it sounds pretty great, why not just try it out.

From that moment on, he began the irreversible path of tyrannically oppressing people, while conveniently tearing open those white moonlights and so-called righteous people’s hypocritical masks.

His goal: wearing the villain’s role to walk other people’s righteous paths, leaving them no path to follow.

- Description from novelupdates