Infinite Mana In The Apocalypse - Chapter 3650 Exodus! I

Hou Niao, devoted to seeking the Dao, found himself mistakenly sent as an undercover agent to the Demon Sword Sect, eagerly anticipating the day he’d be rewarded for his service and could return to the Daoist Sect… Only when he had become a towering figure in the Sword Dao did he sorrowfully realize that there was no one left with the power to recall him!

The Heavenly Dao has shifted, demons rise from all corners, and the powers of Cultivation need to be enhanced. The Immortal Venerable's Order commands us to diligently cultivate, slay demons, exterminate evil, purge demons to protect the Dao, and elevate the might of Huaxia...

God rewards hard work, and there must be rewards for paying.

And no matter how hard you work, you will gain 100%!

So, for things like cultivating immortals, don’t you just need to have hands?

- Description from novelbuddy

A girl who calls herself a demon appeared before a timid student named Fumio Kijima. The girl claims to be a campaign girl from the demon world and she gives him the ability to “summon a room” from nothing but thin air.

At first he doesn’t abuse his power and uses it as a convenient ability in his every day life. But one day he is bullied by his classmates under a false pretext and is made to suffer. In the past he would have wallowed in misery and cried himself to sleep, but now he had a power to call upon.

“I will make them regret it!”

Using his powers to summon his “room”, he begins his era of confinement and brainwashing to achieve his goals.