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

Her step-sister just died three months ago. Now, she insists on marrying Chu Lui, who is supposed to be her future brother-in-law, the mind behind the Chu Enterprise. The world is sure that she, the new bride-to-be, had caused her step-sister’s death in order to seduce him.

Even her own mother says to her cruelly, “Don’t call me ‘Mom’. I don’t have a daughter as vicious as you.”

- Description from Novelupdates

It is the story of a young man who died and was reborn as a level 1 skeleton soldier in an underground world. Follow our protagonist as he struggles to survive in a foreign, RPG-like setting surrounded by danger and monsters. Watch as he levels up and overcomes all obstacles through sheer perseverance and wit, rising to prominence

Tang Feng had been just an ordinary milk tea shop employee before one day, the lady boss called him to her room, and he learned what “hidden rules” really meant...

When he woke up, Lin You found that the world had changed drastically.

Monsters of all races roar and bombard wildly, field magic cards form a deep sea out of thin air, royal tombs, skyscrapers, and trap cards are infinitely possible.

Duellist colleges and universities all over the country are rising, and the miracle secret realm is full of dangers.

This is a world where all people chase cards, and the era of card duelists shines.

- Description from novelbuddy