I, the History Teacher, the Devil Walking in the World

Bai Chen travels through the ancient period of parallel worlds.
I originally wanted to join the cultivator sect in the novel of the previous life and become a cultivator.
However, he unexpectedly awakens the sign-in system of the demon gods that opposes humans.
In line with the principle of no waves and no death, Bai Chen silently signed in and became a demon god.
Bai Chen, who only wants to develop steadily and live a peaceful life.
According to the system task, become the history teacher of Jing'an No. [-] Middle School, and continue to sign in with the same life as a human being.
By the way, you can easily solve the monsters that disturb your life.
Become a peerless master in the minds of students.
until that day.
The cracks collapsed, and the demons invaded in a big way.
The abyss demon god is invincible and descends into the world.
Only then did the students discover that their teacher was actually a demon!