The supporting character's harem is very normal - Chapter 19: I am Charlotte

CautionTaboo 18+Banished by failure and despair, a virgin loser wakes in a new world with a forbidden power—the Lust System. To survive and claim a rare herb that could save him, he must seduce, corrupt, and conquer hearts across worlds. Pleasure is the key to power…and survival.

Life Demon, Order Demon, Knowledge Demon, Fate Demon, War Demon…When various bizarre powers invaded, the world was clearly divided into two distinct sides.Some worship them as gods, walking upon the earth as their spokespeople.Others choose to drink a glass of strong liquor on scarlet nights, and raise the hunting rifle in their hands

Huang Dan’s pain nerve is innately different from the ordinary people. A little tore in his skin can cause him to sweat all over his body painfully to the point of him unable to make a word out.

Somehow, he began to cross world, following Mr. System to do the tasks…

In the first world, Huang Dan realizes what it means to die painfully and to live to die again.

TL’s summary:
MC suddenly transmigrated and is bind to a system, requiring him to solve mysteries. Born with a higher degree of pain sensitivity, he met different people in the different worlds and learns what kind of emotion smiling is.

- Description from Novelupdates

In the King’s game, the [King]’s order is absolute and has the power to create rules. As the owner of a special physique, Gu Huai was selected by the system to participate in the game. “Win the game and become the [King], and you can obtain whatever it is you desire.”

- Description from Novelupdates