It's Not Easy to Be a Man After Travelling to the Future (WN) - Chapter 17: Redemption of Honour Points?

The first time Yan Zhaoge crossed worlds, he landed in a martial warrior civilization that was at the peak of prosperity. He ended up in the book storage building of the the Divine Palace, which collected and preserved the classics of the entire world from all fields of knowledge. However, a world class calamity struck soon after and even the Divine Palace was destroyed.

Yan Zhaoge’s soul once again crossed over, but this time he arrived in the same world, except countless years have passed.

With his brain full of rare books and classics from the era of peak prosperity, Yan Zhaoge’s second crossing over to the present era was like a gamer who was used to playing hell mode suddenly finding himself playing the game on easy.

That was just way too awesome.

But before that, he needs to fix a certain problem.

“I’m not a main character? In fact, I’m actually the main character’s love rival and the antagonistic Mr. Perfect senior martial brother? This script is wrong!”

- Description from novelupdates

“Wang Cheng, we need to practice more!”

“No, I want to guarantee eight hours of sleep every day.”

…

“Wang Cheng, it’s almost nine o’clock, and you’re late.”

“Didn’t you go to work at nine o’clock? It’s still a minute away. Where’s the punch card machine?”

…

“Wang Cheng, what variety show do you want to be on?”

“Is there a fishing variety show?”

- Description from novelbuddy

The most feared Assassin in the world died because of vengeance.