The supporting character's harem is very normal - Chapter 479 Pathogens

Welcome to Freia. A continent where evil magi ruled. Until firearms came, that is. Now the people live free of those demons…

Everyone has a system they just need to meet hidden conditions to unlock it. A blacksmith system may unlock after a human walks by a forge. A master mage may unlock a system after attempting to control the mana in their body. Even something as simple as kicking a rock at a bucket can unlock the marksman system a unique system allowing for perfect accuracy. But what happens when someone reaches the age of fifteen and hasn’t unlocked their system? Walker is about to find out, time is ticking and he doesn’t want to live out his life as an ordinary human; he has dreams you know!

A top hacker was chosen by the Lord God to be reborn into countless worlds, always as an expendable villain.

With no free will, every world became a dead end. Every one of his lives ended tragically.

Finally, after wrestling control of the Villain System, this ace hacker decided to enact revenge. Even if his very bones were rotten, he’d choose to occupy the very heights of morality, if only on the surface.

Thus, he would change his fate as an abused slag.