Is this really a Game?! - Chapter 1 The Prologue

A boy from 21st century Earth, met an accident and later was reborn in Naruto’s Ninja World.
He is born in Uchiha Family and becomes the useless brother of Itachi Uchiha and Sasuke Uchiha…. Let’s see how he changed the Naruto world.

- Description from Novelupdates

A world where awakened individuals with special powers emerge due to a system. At the New Spring Kindergarten infant class, Gru awakens as an S-rank Hunter at the age of 4. Along with this, there is a quest assigned to her… [Quest: A child needs a strong guardian!] Why is a guardian needed? That is because Gru has no mother or father. Gru, who had no family, is adopted by the greatest Hunter in South Korea after many twists and turns, and along with that, new skills are developed… [Let’s try registering a new guardian in the slot!] [Children can earn ‘filial piety points’ through various activities, which can be used in different areas.] Gathering guardians enables faster growth? ‘That’s amazing!’ Alright, I’ll gather all the S-rank guardians!

The most famous deed of this princess was her words to her younger brother Liu Ziye.

When he became emperor, she told him, “Although your highness and I are of different sexes, we are the children of the same father. Why can you sleep with so many different women, while I must be only with my husband? This is so unfair!”

And after the Emperor Liu Ziye heard his elder sister’s words, he ridiculously thought it made sense. So he immediately corrected his “wrong ways” and painstakingly selected thirty handsome youths for her to enjoy.

Chu Yu awoke in the princess’s body and realized that she had obtained a male harem of three thousand; should she take just one to drink, or keep all of them?

- Description from Novelupdates

Xu Yangyi, an 18-year-old high school student, for the reason that his older twin sister eloped with her girlfriend on the wedding day, was forced to be the surrogate bride by his own father. As a result, he became the wife of the man who should have been his brother-in-law.“You’ve gotta look at me carefully. I’m a man.” Xu Yangyi glared at He Jingyan, who was still getting fresh with him though he already knew Xu Yangyi was indeed a man.“Man?” He Jingyan fiddled with Xu Yangyi’s face with his big hand and gave him a sly smile, “You look identical with your sister, so it doesn’t matter!”