Pushover Extra Trains the Villainesses - Chapter 4: Master of the Dark Sword II (2)

He is a young man without a spirit root. It is believed that this denies him the chance at cultivation. However, a mysterious lady imparts a Supreme Demon Classic to him and from then on, he starts his path of cultivation.
He undergoes a total transformation to emerge as the most fearsome and powerful fiendish demon in his era, that even immortals and fiends are fearful of him, and saints are at his beck and call.
Mastering the Supreme Demon Classic is the turning point in his life. He is able to unleash his immense and divine power from within, illuminating the entire universe!

- Description from Novelupdates

I have experienced all the eight sufferings of this world.

I do not ask for nirvana, but for you.

Wild and hard-to-tame demon (gong) x cold, ascetic and childish immortal (shou)

- Description from Novelupdates

Host: What is your dream?Lv Xiaobu: To eat and do nothing, to do as I please.Host: Then how did you become the world's richest man?Lv Xiaobu: How would I know? You ask a spendthrift how to make money? Really! I want to go back to sleep.Host: Please don't...Lv Xiaobu: Tip, five thousand.Host: Kneeling and sending off Young Master Xiaobu, may Young Master Xiaobu rule the world forever!Lv Xiaobu: Wahahaha!

Cho Kang-hyuk, the owner of a large fitness center, woke up to find himself a young disciple at Shaolin Temple.