MTL - My Youth Began With Him - Chapter 4765 Extra number (four)

In a world where human and monsters relied on mystical fruits and their inner power to fight for dominance, a lost soul was thrown, given the powers from all the other worlds he’s known. But there was a catch; he had no control over what power he would get! With knowledge beyond that of most, he sails his path to the top of the one piece world!

- Description from Novelupdates

It has been adapted into comic：CEO’s Sudden Proposal / Flash Marriage Deep Love

She didn't understand why he took her to get married at first sight. She was just friendly to his daughter at the hospital, but she did not expect that his daughter haunted her to be her mother. It's only the first day of their meeting!

She thought he married her only because of his daughter, but in fact, he was deeply attracted by her kindness and simplicity, and he loved her deeply.

For the rest of her life, Will she love him like he love her?

The romantic comedy light novel series centers on the gaming lives of various high school students who play video games, including: Keita Amano, a lonely young man who loves video games; Karen Tendō, the beautiful president of the video game club; Chiaki Hoshinomori, who constantly fights with Keita; and Tasuku Uehara, who puts on a facade of being satisfied with his life in the real world, but he in truth loves video games.

A data loving young man from Earth has an accident which transports him to a dark land filled with terrifying creatures and magical powers. Fortunately for him, he has a Biological Assistance Chip to ease his path. However, things in this bizarre and strange world are not always as they seem, and, though it is a tremendous asset, the chip doesn’t always work as expected. With all of the crazy creatures and magical mayhem around him, one can only wonder what the future holds for this young man…

- Description from novelupdates