CROWN PRINCE'S CONCUBINE - Chapter 643 - 643 White Tiger

One day, a mysterious tower suddenly appeared in the city. The people decided to call it a dungeon, and while it was full of rugged terrain and dangerous monsters, it was also a land of opportunity, where countless treasures awaited. When Sejun, a young man living an ordinary life, is invited to the dungeon by chance, he is thrilled at the prospect of becoming rich, but he is stranded in a hidden area of the mysterious tower. All he has is a few seeds and his body. Now Sejun must farm, collect resources, and figure out his own survival strategy!

Pet shop owner Tang Wan was accidentally reborn into an interstellar world. When he opened his eyes, he found himself automatically married to a vegetable via the StarNetwork. A social status worth ten billion yuan; but with an unconscious husband, he was unable to withdraw any money. Tang Wan held the empty position of the First Gentleman, but was, in fact, a poor man.

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

Until the time of him becoming the master of the lowest rank in the order of rankings, the lonely side of his life without luck was changed.