Transmigration: Raising the Child of the Male Lead Boss (WN) - Chapter 488

Ethen Cole travels to an era where everyone battles with pets. In a world revived by spiritual energy, danger and madness run rampant. Humanity relies on battle pet masters to establish bases and unite for survival.Before the college entrance examination, Ethen Cole is framed and expelled from school, losing his chance to study at the Battle Pet Academy. Just as he feels despair, the Battle Pet System for battle pets activates.“Ding! The Blue Riolux has evolved into a Emerald eyed Riolux!”From then on, Ethen Cole begins his legendary career as a battle pet master.

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

Mimizuku, a small girl with chains on her wrists and ankles and the numbers “332” branded onto her forehead, wanders into the Forest of Night seeking to be eaten by a monster. However, when the ruler of the monsters, the mysterious and beautiful “King of Night,” refuses to eat her, she tries to formulate a way to convince him otherwise.

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.