Naruto: I'm Nine-Tails and My Host is Kushina - Chapter 171

The course of commitments never did run smooth.

After dying on Earth, the King of Mercenaries is reborn as Su Mo in the Firmament and Continent. In this brand-new world, Martial Art is the way of life, and the strong set the rules.

Having awakened a Martial Soul of the lowest rank, possibly meaning he will never go far as a Martial Artist, Su Mo is determined to rise to the top again nonetheless.

However, misfortunes never come singly. The love of his life is soon taken by one of the most powerful forces in the world. With no time to spare, watch as Su Mo overcomes all odds and struggle on the verge of death countless times, in order to meet his love again.

As the protagonist reaches the top in that world, he has to take on more responsibilities and face new challenges.

Follow Su Mo on his relentless journey to become stronger for the sake of those important to him, and uncover the deep, dark secrets and plots in the vast universe.

- Description from Novelupdates

Full NTR*[Warning: This story is strictly 18+ and contains extreme NTR, explicit sex, mind-breaking corruption, and brutal violence. It is not for the faint of heart or those seeking a heroic journey. This is a tale of domination, destruction, and absolute fear. Only mature audiences who can handle dark, merciless storytelling should proceed. Read at your own risk.]***This story is a dark and ruthless descent into a world where power, manipulation, and betrayal reign supreme. A tale of absolute dominance, it follows a cunning and brutal protagonist who uses seduction, deception, and raw strength to corrupt, control, and destroy. No one is safe—wives, saintesses, and proud heroines fall, their purity tainted, their loyalty shattered. Betrayal is inevitable, and those who stand in the way meet gruesome, indescribable ends.**Brutal violence as Jin leaves a trail of broken heroes, shattered empires, and subjugated goddesses in his wake.

A long time ago, the decayed main god space collapsed and disintegrated, and the wreckage was scattered in parallel universes, giving birth to a new space…

Countless ‘story worlds’ under control have also fallen into the void, regained freedom, runaway out of control, elevated to reality, and turned into reality.

At the same time, these “worlds” are polluted and corroded by the void, giving birth to greater fear and filth…

…

The space of birth feeds on the world.

They compete with each other, their tentacles penetrate through dimensions, invade different time and space, search for the legacy of the main god, drive the apostles to be minions, greedily tearing, seizing, devouring, and reclaiming one world after another, so that they can return to greatness.

…

The innocent eating melon and white waves with the legacy of the Lord God accidentally got involved in the parallel universe “Paradise of Fire” during a cross-border call.

After forcibly binding the demi-human blood, he became an excellent tool man who can repeatedly die, starting the legendary ‘dimension invasion career’.

- Description from novelbuddy

The story is about a a hitman, Who dies because of his own recklessness and transmigrates into a game he used to play after his retirement as a hitman.I'm not gonna spoil any further, but i might answer few of your questions.Is MC overpowered?Nope, he'll become strong over time and all battle he'll fight will be because of his effort and techniques.Is there magic and adventure?Yes! It have both magic like normal isekai with adventure and fighting with monsters and many other things. There are other important things like “Essence Stone” But let's talk about it in the chapters.There will be harem?Not really, He will be in contact with many beautiful female and males but one waifu but i haven't decided yet.All i can say is, give it a try, I'll try my best to make it worth your time.