After Being Reborn, I Tortured The Vicious Sister-in-law - Chapter 405 - The Ancient Book

A master assassin transmigrates into an interstellar era.

[WSA 2025] To confront the threat posed by monsters and demons, humanity summons a hero endowed with a mysterious system and an unrivaled capacity for evolution. He becomes the last bastion of hope for mankind. However, one of his mistakes gives rise to a calamity far worse than the Demon King.This calamity is conceived in a dungeon, abandoned as a fetus by its mother, and raised by the Demon King himself. Upon the Demon King's death, all the restraints he had placed upon the creature are shattered. Thus, the hero's nameless son begins to lay waste to everything. The greatest calamity the world has ever known is born.

What if the president always coerces her to do “hard work” on the grounds of deducting her salary?
To do or not to do?
After finishing the work, Lin Sheng silently took out his mobile phone, opened the circle of friends, and pressed down word by word:
The president asked me to work at her house again!
President, she has a little white face!
The woman behind the successful woman is me! it’s me!

Domineering domineering president X small staff
The daily life of the president and the staff is so sweet and sweet~

- Description from novelbuddy

Long Fei, a cross-timer and doujin, is an otaku who traveled to another world. In the original world, he was an otaku fan of Gundam and military science fiction.

He died in an accident and was reincarnated into another world. The Gundam works he had read before his death and the techniques in various military novels could be brought to another world.

How would he use the Gundam that Long Fei created? What waves can be caused in this different world?