Black Tortoise God of War - Chapter 28

“I can clear all your debts, but you have to substitute me in my marriage…”

When Liang Dou Kou was diagnosed with cancer, she formed a contract with Qin Zhi Ai to substitute her in the time she would be absent, including her marriage with Gu Yu Sheng.

Initially, Qin Zhi Ai suffered under the cold and harsh attitude of Gu Yu Sheng, who mistook her for Liang Dou Kou. But his heart gradually softened and he fell in love with her.

Just when he thought that he could live happily ever after with her, it is time for Qin Zhi Ai and Liang Dou Kou to revert their identities, and Qin Zhi Ai evaporated from Gu Yu Sheng’s life.

Months later, Gu Yu Sheng meets someone who possesses the gaze of Qin Zhi Ai who captured his heart…

Xuanyuan was reborn into a strange new world where training to be a Xian was a cornerstone. There was however something ancient dwelling inside his body. He could now devour all of creation…

The traitor Gu Mang returned to his home kingdom again. Everyone rejoiced in his banishment. It was said the one who hated him most was his closest friend – the cold and stoic Young Master Mo.

A rumour: Young Master Mo prepared three hundred and sixty-five methods of torture to try on Gu Mang, enough to play with him for a year without repetition.

But what’s the truth then?

Well the truth is even more unspeakable–

Mo Xi’s identity: the most abstinent commander of the empire.

His relationship with the traitor Gu Mang: they’d slept together before.

- Description from Novelupdates

Crossing to One Piece world, he became Roger’s younger brother.