Douluo Dalu 2: The True God King - Chapter 374: [DD2]:

How does a half-grown mountain village boy like me end up bizarrely becoming the grandmaster out of nowhere?Source: Web...

A continuation from where High School DxD Volume 25 left off.

Bai Aoxue, the best mercenary in the 21st century, is accidentally sent back to the Chengxi Dynasty in Great Continent due to an explosion in her mission, and trapped in the first daughter of Prime Minister. After her rebirth, she is set up by her father to marry the 5th prince Jun Yeyan who wears a mask all day long.
In the face of bloodthirsty enemies, discord between brothers, collusion among courtiers and invasion of enemy state, can Bai and Jun resolve the crises? What will happen to their political marriage? How will the fierce battle for the throne end?
With many twists and turns, the book brings you to experience palace revolution, love and hatred thousands of years ago.

- Description from Novelupdates

Description For a million worth of contract, she became a surrogate mother. He was the chief executive of the Empire and she was of lowly birth. With her adoptive father’s business falling into crisis, she agrees to his contract. She gave birth to twins: the older brother is healthy, while the younger brother didn’t breathe out. Fulfilling the contract with a huge monetary sum as the reward, she disappeared from his eyes. Six years later – he was still the cold high-profile president, but when she is accidentally imprisoned in the cage of his golden birds he pressured her harder and harder: “Woman, do not think you can escape my hands!” The old-fashioned man: “Mu Yazhe, you’d better leave her alone, this is the child’s mother!” The man becomes frightened, questioning the reason this child’s features bears such resemblance to… Associated Names 一胎二宝：亿万首席爱妻入骨