I'll Teach You, Marianne. - Chapter 118 - The Rivalry Of

In a world where dungeons were an essential part of it, Rein was trying to conquer as many as possible. They were the key to gain powers in the fastest possible way. So, to reach his full potential and to become the strongest, he became a great dungeon conqueror.With his trusty friends and lovers, he was definitely going to reach the peak alongside everyone. Join Rein and see how he went from strong to stronger and then the strongest.__________________1. The harem would not be too large(I'm not sure how many but probably just 4-5 main and few other here and there). All the girls would be getting their time and story.2. The story is starting when the MC is in the middle of his growth stage and not at the very beginning. But his beginning will be mentioned in the story in some form.3. I don't think I need to mention this, but obviously it will not have any NTR, rape or that kind of stuff. It is actually quite a wholesome story focusing mainly on adventure, action and bit of romance and slice of life.

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

One of the six people called heroes, Raid, fought alone against the Devil, and ended up dead.

After meeting with a suspicious god, he woke up again and found out he has born again as a baby.

Moreover, as a daughter of his former companions.

In order to regain his former power, Raid/Nicole has to go through a life of hardships to reach the ideal he aims for.

Heed my call! O’ Dragon of Eternal Sin, the Progressive Disaster, the Forerunner, the Land of Eternal Peace, the Flames of Soul Burning, He Who Owns The Deep Soul, the Sound of Origin, the First Cause of All Things, the Principle of Circles… o’ great Negary, your servant calls for your return!