House of The Dragon-A God Amongst Men - Chapter 2: The Man From The Stars

The best way to declare war on a spy as an ordinary person is to become a spy as well.As a spy, if you want to go to war with a powerful espionage organization, join an equally powerful espionage organization.If you are unable to join any powerful espionage organization, then establish your own espionage organization and fight until destruction or victory.This is the war of spies, telling the story of how a group of ordinary people achieved extraordinary success.

I once believed I was the heroine of a modern fairytale, blessed with beauty, wealth, intelligence, and a powerful legacy. Men adored me, women envied me, and I was engaged to the most desirable man, Cole Fay. My life seemed perfect, a dream where I held the starring role. But on my eighteenth birthday, that illusion crumbled. The truth hit me hard: I wasn’t the protagonist, nor even the villain or a side character. I was just cannon fodder, a disposable part of someone else’s story. But when fate recognized the cruel joke of my life, I was granted a second chance. This time, I’ll write my own story, living for myself. And this time . . . I will never love you again.

A man was transported to Ancient China and eventually became a servant of a declining household without a male heir. He utilized his wits and modern knowledge to help the household and eventually become trapped in the sea of political turmoils of the period.

- Description from Novelupdates

Xia Yan passed through to the world of Bleach and became an eleven-year-old boy. He was rescued by Renji and Rukia in the Seireitei, and he was studying at Shin’ō Academy, and he was a student of the same class.
He is a top student of the Shin’ō Academy, and he is vying for strength by various teams. In the end, he has entered the first team of secret mobile maneuvers.
He will use punishment to kill every person who tries to threaten the martyrdom and protect his loved one.

- Description from Novelupdates