There must be something wrong with me - Chapter 16 - 13: End and Return_2

I was reincarnated into another world, and I’ve brought the Horadric Cube from Diablo II with me.
Being a knight is cool and all, but being a wizard is pretty neat as well.
So, which one will it be?

- Description from Novelupdates

Forcefully brought over from the modern world to an alternate world, Wang Chong felt detached and lived his life aimlessly.

However, when calamity struck and he saw his family and everything he cared for being torn apart, he felt regret.

Thus, he stood up and eventually became the Grand Marshal of the Central Plains, leading an army against those who seek to destroy all he cherished.

Yet, despite all his efforts, it was already too late to reverse destiny.

But before his death, a shooting star, the same one which brought him to this world, appeared before him, and he was given another chance to undo his regrets.

- Description from Novelupdates

Transmigrated into the novel you read and became the heir of the Duke, only to be trampled under the protagonist's foot?Passerby villain?Appeared in only one chapter?“Who are you looking down on?”Ian cursed his destiny and vowed to change everything.[Ding!][A new quest has been activated.]'Oh? Do I have a system? Even better.'[Basic Quest 1: Don't let your flower slip through your fingers.]'Nice, I won't let go of her anyway.'...[Basic Destiny Quest 1: Can You Finish What You Have Started?]'Bring it on!'...[Ding!][You are at an important fork in your fate.][Unique Destiny Quest: Fight with all you have.]'Heh? Who are you looking down on?'As Ian completed one quest after another, he also inadvertently began to fall into a vortex of the unknown. He discovered there was more to this world than described in the novel.'Damn it! These suspense and twists, one after another, are killing me!'---Tags: Smut, 18+, Harem, no incest, weak to strong, Romance, Wizard, Magic, Knight, System, Multiple Planes, Elf, Demons, Monsters