The supporting character's harem is very normal - Chapter 328 Thank you, Akna.

[WSA 2024 Entry][3-5 daily chapers update]“BOOM!”Tron's body smashed through seven mountains, shattering them to dust as shockwaves destroyed everything in a twenty mile radius!But by a stroke of luck, he managed to survive.[DING!][Host's has received an attack from a Crimson Void Dragon God][Host's muscles will begin to adapt to the same level of power.][DING!][Congratulations Host, You now possess the strength of a God-level Magus!]* * *In a world where magic reign supreme, Tron Mahoraga was rendered crippled, his Magical Cortex destroyed, used as an experiment for an Arch Magus.However...[Ding! Congratulations! Ultimate Evil Matrix System Activated!][ERROR!!! Arcane Cortex not detected!!!][Multiversal Law Of Survival Activated][Randomly increasing one of host's ability... ][Ding! Supreme Muscle Adaptation acquired: Host's Cells can adapt 10,000× times faster than regular human]

I became the villain in the story of a hero.

So I was about to quit after fighting the main character.

But she’s obsessed with me. Why…?

The empire has turned into the land of the undead due to a spell gone wrong. God summoned heroes from countless worlds to purify the empire and plant new hope. Lee Shin Woo, an ordinary earthling, was also summoned. As an undead, that is.

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.

During the first known year, a magical mountain descended into the world from the realm of the Gods. Carved on this enormous mountain was a message: ‘Heaven Prevails’…

After the Grand Descent, a name that was given to the descending of the mountain, the Three Great Sages made their ways to Mystic Mountain where they learned to harvest what we now call magic, establishing the Mystic Cults and eighty-one sacred shrines to help aid mankind with the cult’s mystic powers against the eternal fight to the death with demons.

- Description from Novelupdates