MTL - My Wife, King Arthur - Chapter 662 Kana and Lucy

Every time he dies, Ethan Hill gains a little more power.Earth was chosen for Integration, but Ethan knows from the second his Trial begins that the Integration is a lie. These creatures giving Earth the 'honor' of access to their Interface want something from Earth - he just doesn't know what.Now he's trapped on an alien planet and lost in a time loop, fighting for strength and for his own humanity.One thing's for sure: He'll die as many times as it takes to tear it all down.

In novels with a stud there is always a Senior Martial Brother like this:

In the early stages of the novel, his innate talent is high, his cultivation is good, his appearance is handsome, and he has an intelligent, cute younger Martial Sister as a fiancée.

In the middle stages of the novel, he is caught unprepared and defeated by a young disciple (the protagonist) in the sect who’s hardly remarkable at all. From then on, he falls from his godly altar and loses his brilliance. Even his young Martial Sister leaves him for someone else.

In the late stages of the novel, he continues to turn dark, going down the Demonic Path and becoming the major villainous boss. However, the protagonist still ruthlessly defeats him and his soul is eternally sealed.

Once Qin Mo opened his eyes, he discovered that he had become this Senior Martial Brother.

- Description from Novelupdates

“Only by enduring 2¹⁴ trials can one awaken the ancient power sleeping within the Key of the Star Prison, and become the most powerful being in the universe.”Timothy, the youngest Demon Lord in the history of his race, saw these words emerge after he touched the Key of the Star Prison, the most powerful artifact of the demon race, handed to him just before the old Demon Lord's death.According to the demon race's records, no Demon Lord had ever achieved this.However, over a span of a hundred thousand years, Timothy had easily passed 16,383 trials.Now, once again, he turned the Key of the Star Prison, and an unknown force mistakenly sent him to a brand new world, transforming him into an unknown and seemingly worthless demonic cultivator disciple.And the formidable opponent he was about to face in this world was the powerful Goddess Sylvia.When Goddess Sylvia received the challenge Timothy handed her, her cheeks flushed...“My dear Sylvia, I want you to know how deeply I love you. My heart belongs to you, now and forever.”