Shadow's Oath - Chapter 98

Once an unsung slave; Yur’s existence was defined by blood, pain, and chains. That was until he stumbled into Zulmasharr, the realm of demons.In the depths of despair and agony, a near-death encounter unsealed the terrifying truth of his existence; he is no mere mortal. A cursed hybrid of human and demon; Yur’s survival was only possible through the bloody rebirth of his Ashkavaal bloodline and the awakening of his sinister cultivation system, Zul.With Zul, Yur can rear demons for rituals, harvest their power, and dominate the chaotic world around him. But freedom comes at a cost. As the incognizant successor to an ancient being, his every step is burdened by the weight of a destiny he never asked for. Yur craves only one thing: to stay free, unbound by demons and men. Yet his growing power and severed bloodline ignite the fascination of forces that would see him enslaved or slaughtered.Yur must steer through a world of demons where trust is a fault, survival is animus, and his very existence is a blemish. Blood will pour, flames will revolt, and demons... they kneel or die. But in the end, is freedom attainable for the bearer of a bloodline forged from blood and ash?Will Yur vanquish his fate or will it condemn him?

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

The engagement of the most adored daughter of the Li Family was broken off. Her furious family members railed against the heartless man and vowed to make him pay the price. * Later on, Li Qiao met her ex-fiancé’s big brother by chance. Some said he was the most mysterious man in Nanyang and his name was Shang Yu, aka Shang Shaoyan. While some others called him the overbearing and obsessive underground Overlord of Nanyang from whom everyone should stay away. Standing in the misty rain, Li Qiao gazed at the ruthless and untamed man with a shallow smile, said, “Hello, I’m Li Qiao.” She would become her ex-fiancé’s sister-in-law, if not wife. * Li Qiao and her ex-fiancé met again on the street several months later when he sneered at her, “Are you following me? Haven’t you given up hope yet?” A harsh voice berated him from behind, “Show some respect to your sister-in-law!” From now on, only one rumor was circulating in Nanyang City – The merciless Overlord of Nanyang had one woman he uncritically doted on. Her name was Li Qiao.

Ren Kuroda, a college student and hardcore gamer, finally conquers Eternal Souls: Last Judgment, an unbeatable RPG, only to be met with a strange message on his screen.“Congratulations, Champion. Would you like to unlock the bonus stage?”When he clicks “Yes,” he is transported straight into the game world, reborn as Terence Ross, the overlooked third son of a minor noble family. Realizing he’s just an extra in a world teetering on ruin, Ren trains relentlessly to survive the coming chaos.However, life wasn’t smooth sailing.He was soon engaged to Lilith Underwood, the girl destined to become the game’s final boss, the Third Great Calamity. To avoid her devastating future, Ren takes a risky approach, trying to make Lilith emotionally dependent on him in the hopes of anchoring her humanity.Yet, his plan backfires spectacularly. Lilith’s attachment becomes a fierce obsession, one that could be just as dangerous as her dark powers.Now, as doom inches closer, Ren faces a double-edged crisis. He must keep Lilith’s powers in check while somehow surviving her unrelenting need to keep him by her side.In a world where even heroes fall, can an extra rewrite his fate? Or will he be claimed by the calamity he tried to prevent?