My Backyard is the Tang Dynasty - Chapter 356: Space-time crisis!

「Shimizu-san, you dyed your hair black.」「Ah, yes.」「Why did you dye it all of a sudden?」「Because…yesterday…」Shimizu-san, who sat next to me and had dyed her hair from blonde to black gradually lowered her voice, slightly blushed, and laid her face down on the desk.

A decision can destroy the sun, moon and stars. A finger can kill the Heavenly Overlord. While chatting, the Heaven and ten worlds can be annihilated.

Seventeen-year-old Hajime Nagumo is your average, everyday otaku. However, his simple life of pulling all-nighters and sleeping in school is suddenly turned upside down when he, along with the rest of his class, is summoned to a fantasy world!

In a world dotted with World Entrances to a demon world, demons have invaded humans for centuries. Humanity has united and one of the most ancient sects in the world, the Archean Mountain Sect, has set up an entire education system in the form of Dao Academies and defenses at the World Entrances.