Game Design: Who Rated the Games as Very Easy? - Chapter 11: The Path of the Guilty

A supreme expert in the Immortal World had died, and a strand of his soul returned to its original body on Earth. Tang Xiu discovered with amazement that ten thousand years passed in the Immortal World, yet only a single year passed on Earth.

Ruthlessly betrayed by his lover and trusted friends, Tang Xiu found that his soul went back to his previous body on Earth, and, despite he spent 10,000 years in the Immortal World, just a year has passed on Earth and many things have changed. Having an unsurpassed knowledge, Tang Xiu will protect his loved ones and go back to the Immortal World to take his revenge.

- Description from Novelupdates

People keep assuming I’m some kind of evil mastermind.But seriously, I’m just a son-in-law freeloading off my noble wife’s family.…Why does everyone look so suspicious?Wait—don’t tell me. Is it because of my squinty eyes?!

The world is terrorized by the powerful Black Witch who has been sealed in the moon. Every ten years, the night of Hexennacht arrives and a chosen witch must battle the Black Witch in hopes of finally defeating her.

As the current decade’s Hexennacht approaches, a mysterious girl named Kagami Kagami arrives and meets Horinouchi Mitsuru, the daughter of the previous Hexennacht representative.

It takes place between Kyoukai Senjou no Horizon and the City Series, two other series by the author.

He was the merciless Soldier King on the battlefield who sent shivers down the enemies' spines; he was the soldier scoundrel in his squad who could make anyone both cry and laugh; he was the Big Brother everyone in the urban underworld aspired to be; he was the male god in the hearts of young girls and beautiful women; he returned with a mission...Uniting the underworld, establishing an economic empire, he vowed to become the supreme overlord of this world...To prevent the world from destruction, to protect world peace, to implement love and truth's evil, the lovely and charming antagonist, he is Xiang Yu, and he speaks for himself...