Descent of the Demon Master - Chapter 1131. Getting Some Rest (1)

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!

Suddenly a high school student Subaru Natsuki has been summoned to another world on the way back from the convenience store. With the biggest crisis of his life being summoned to another world and no sign of the one who summoned him things become worse when he is attacked.

After breaking up with his girlfriend, he accidentally acquired a genius system and rose from there against the heavens, becoming invincible..

- Description from Novelupdates

The low-ranking behemoth, the iron mountain is invincible in the horizontal push, and it is called the king of the backing.

- Description from novelbuddy