Douluo Dalu 2: The True God King - Chapter 179: [DD2]:

In 2076, technology did not bring a better life to people, but instead became a tool used by the rulers to exploit.Arthur traveled to such a cyberpunk world and accidentally obtained the check-in system.You can get a variety of technological knowledge just by signing in.Before he could do anything, he unexpectedly discovered that the original owner was already married and even had an older son.Arthur: “The freedom of marriage is sacred and inviolable. That's not my wife.”Why are you saying that my wife is Gloria and I have an older son named David?Arthur: “How can a human being abandon his family and his son? Just go with peace of mind as the original owner. After your death, your wife will be taken care of by me, so don't worry about it.”

When proposing, Gu Ningxi praised Tao Xinhe for her “perserverence and responsibility”, and on his wedding day, he vowed in public to “be one and only pair for life”.

Tao Xinhe believed it, believed it deeply, and devoted herself to being a good, virtuous wife for her faced blind husband.

Knowing that Gu Ningxi sees everyone as a tile face, she does not change her clothes or incense, and finally let him rest assured to embrace her;

She accompanies Gu Ningxi to the banquet and party, and mentions the names and origins of the guests, so that he can get rid of his arrogant name;

She accompanied Gu Ningxi while he misses his mother, endured the cold face of her grandmother, and dealt with the entanglement of her uncle and aunt, so that he would have no worries.

Yet nothing compared to that— Gu Ningxi could see Mo Qiqi’s face. In his eyes, only Mo Qiqi was vivid and pleasant, and the faces of the others were blurred.
He focused his eyes on Mo Qiqi, coaxed her softly, and allowed her to touch him. For this reason, he deceived and neglected his wife, and he couldn’t recognize Tao Xinhe who had changed her clothes.

Tao Xinhe’s heart died, determined to go, she left a letter of divorce. Her father and younger brother treated her like a jewel, she regained her spirits, and when she heard the news of her ex-husband taking Mo Qiqi into the mansion, she only smiled.

- Description from Novelupdates

The MC entered the body of the An family eldest son, An Ziran, an arrogant 16 years old boy who weighed 78 kg (~171-172 lbs), who only knew how to eat, play and sleep. Seeing his current body, An Ziran decided his first priority was to LOSE WEIGHT!

Three days later after he became An Ziran, An Ziran’s father and his biological mother died, which meant as the eldest son he had to take over the family business.

Beside his legitimate first wife, An Ziran’s father also married 3 others women, who all wanted to take over the An family fortune but only the eldest son could be able to touch it, therefore they have to depend on An Ziran in order to live a comfortable live.

An Ziran’s father also had an older brother who is always planning to steal the An family fortune. The elder brother of An Ziran’s father and the woman he married had powerful connections. In order to save the An family fortune, An Ziran has to find a golden thigh to cling on. The butler told An Ziran that there is an engagement between the An family and an influential family. Therefore he takes his sister to that family house to make a connection.

However, during their journey, An Ziran’s younger sister overheard that the son of that family is UGLY, so as a beautiful and spoiled young lady coming from a rich household, she didn’t want to marry him and decided to run away. Without any other choice, An Ziran had to take his sister’s​ place and marry that man, who told him that he would let him go soon, but lied.

- Description from Novelupdates