I Really Want to Become an Immortal

Thousands of years ago, demons from outside the world invaded the lower world, causing all life in the lower world to be devastated and the human race to almost perish. Thousands of years later, the devil is dead. A Buddhist kingdom has been built on the plains of the west, the old Taoist sect in Zhongzhou is still in its prime, the alien races in the northern plains are thriving, the Southern Xinjiang Academy and the Taoist sect are fighting against the Demon Valley, the Dragon Palace in the East China Sea is still drunk and intoxicated, and I don't know what is going on with me... Xiao Ping traveled to the lower world for twenty years. Originally, these things had nothing to do with him. He was weak, was not taken seriously, and was even rejected by his master, and gradually became desperate for life. Until this day, the system in his body awakened, bewitching him step by step. "Demon System", as long as he follows the will of the Demon God, the entire lower world will tremble under his feet. Because by then, he will become a demon! "Master, this is much more useful than what you taught me..."