Tower: Rebirth of the Absolute Demon - Chapter 71: Ch : God of Death? He’s dead.

Zhang Siyi, a graduate student of architecture department went back from overseas seeking for work, he had a heated fight with his ex-girlfriend in a cafe. Angered, his ex-girlfriend was about to splash a cup of coffee in his direction but he managed to dodge it. As he stepped back, the misfortune was met by the handsome guy next table instead.

Suddenly a high school student Subaru Natsuki has been summoned to another world on the way back from the convenience store. With the biggest crisis of his life being summoned to another world and no sign of the one who summoned him things become worse when he is attacked.

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

She was the heiress of the influential military and political Shen family. She possessed an exceptional face and a cool demeanor. Although she was the apple of her family's eye, she was disliked by her birth mother.He was the only heir to the immensely wealthy and powerful Fu family. Powerful, arrogant, and cold, he was the captain of a stealth corps and the youngest commander.To fulfill her grandmother's final wish, they got married in a flash. Initially, she regarded the marriage as a mere contract, but she did not expect to elicit his utmost admiration.