Toaru Majutsu no Index - Volume 2, Chapter 1: A Tower of Glass. The_Tower_of_BABEL.

An accident gave Su Hao the ability to reincarnate infinitely.

But who can tell him why he can’t live past five years of age every time he is reincarnated?

The universe is dangerous and unfriendly to children.

Su Hao decided on his first small goal — to become an adult.

“How could I not even become an adult!”

…

Amidst Su Hao’s millions of reincarnations, one time after another. After obtaining enough knowledge, he discovered the way to become a god.

This is a mortal’s path to divinity. Maybe… you can too!

Liu Duo was a young girl whose grandmother sold her to four brothers with the intent to be a bride. Unwilling, she ran away the following night, only to fall unconscious while trying to get away. Unexpectedly, however, she was reborn with the spirit of a 25 year old woman, also named Liu Duo.

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After a vacation, when she returned to her country she caught her fiancé cheating. She angrily left and disappeared.

Five years later she returned with her talented kid. Afterwards, her son participated in the piano competition. Unexpectedly her son actually came looking for his father.

“The camera on this side, take me to take a look! My name is Xiaoxi my mommy is called Tang Siyu and she’s very pretty! I’m four and a half years old this year. I’m looking for my father, you probably look like me, please be sure to contact me, oh!”

After that, he was gone from the front of the camera again and said, “Oh, I’ll wait for you!”

In the background, a woman became mad. A few days later, a mysterious man came to their doorstep and claimed to be Little Xi’s father.

Tang Siyu looked at this tall and handsome man, who her son was a carbon copy of, and then became angry.

Five years ago, the bastard who pinned her down was him?

- Description from Novelupdates