Kujibiki Tokushou: Musou Hāremu ken - Chapter 123

This story is about a rookie researcher, who was forcefully dragged away from his restful life, compelled into facing various killers and zombies, always having to risk his life at the brink of death, and finally becoming an advanced researcher that is acclaimed by all. And throughout his adventure, he met an alluring(?) killing machine, who he started to have fantasies on after they had an accidental kiss…

Xiao Yan: Did I fall for him? But he’s a man!

Maya: Who knows…. maybe it’s the other way round?

- Description from Novelupdates

Big Player can't reap without sowing!Have you ever seen a transmigrator forced to risk their life over copying a novel by the system?Have you ever seen a transmigrator who has to endure physical punishment by the system for quoting a famous line from their past life?I just freaking want to make some money, why's it so damn hard!System, do you dare stop messing around? I might be a fake transmigrator for all I know!……

This novel is also known as Only I Level Up

10 years ago, after “the Gate” that connected the real world with the monster world opened, some of the ordinary, everyday people received the power to hunt monsters within the Gate. They are known as “Hunters”.

However, not all Hunters are powerful. My name is Sung Jin-Woo, an E-rank Hunter. I’m someone who has to risk his life in the lowliest of catacombs, the “World’s Weakest”.

Having no skills whatsoever to display, I barely earned the required money by fighting in low-leveled catacombs… at least until I found a hidden catacomb with the hardest difficulty within the D-rank catacombs!

In the end, as I was accepting death, I suddenly received a strange power, a quest log that only I could see, a secret to leveling up that only I know about! If I trained in accordance with my quests and hunted monsters, my level would rise.

Changing from the weakest Hunter to the strongest S-rank Hunter!

- Description from Novelupdates

It has been six years since the game to decide the world’s fate began. The strongest player, Hero King Kang Yoosung, who has never lost his first place as the top ranker, greets a new season. “It was… over for me a f*cking long time ago. I’m just doing this for the money.“ [Provocation stat increasing exponentially!] [The Clown Lord expresses satisfaction with contractor’s behavior!] The survival journey of a player with insane talent begins now!