Toaru Majutsu no Index: Genesis Testament - Volume 2, Chapter 2: Black Pill, White Snow — and_RED_Rose.

Jacob Steve, an Old Man, died at 116 after living a whole life.

But Jacob always had a dark side, which he always suppressed and hid from others.
However, in the later years of his life, when death was inevitable, he understood there wasn't any point in having wealth, knowledge, or desires if you couldn't have a life to enjoy them.

He became obsessed with fabled immortality and devoted his reaming life to extending his fleeting lifespan, but just like any other failed.

However, he mysteriously got another chance at life and found a way that led to fabled immortality.
But he was also forewarned that the way led to it was filled with blood and darkness!

In the end, Jacob chose it anyway with no way of going back, and it was also the start of his suffering and his icky, brutal journey toward the 'Immortality' he wanted so badly!

Once through the pirates, Lu En became the son of Monkey d Dragon, a grandfather named Monkey d Karp, and an unreliable and neurotic younger brother named Luffy.

Fortunately, the ghost back system is activated!

The completion of the ghost back is 10%, and the training effect is increased by 100 times!

The completion of the ghost back is 20%, and the training effect is increased by 1000 times!

…

One day, Lu En, a ghost-backed master, appeared in front of Luffy who was shouting to go to sea, and made Luffy cry on the spot.

Luffy: “The pirates in the sea are all monsters like my brother? I don’t want to go out to sea!”

Garp: “For a long time, the two boys, Long and Luffy, with small arms and calves, I really doubt that they are not my sons and grandsons. Like Lu En, they are the grandsons of the old man!”

Warring States: “The strongest creature in the sea, land and air is Kaido? No, it’s Lu En!”

- Description from novelbuddy

In the late years of the Daqian era, tyrants roamed freely, war erupted endlessly, and the people could not sustain their lives.After transmigration, Chen Jie finds himself as a drunken gambler with a pair of unfortunate sisters at home.The elder one, Su Yunjin, is his wife, and he also has a five-year-old sister-in-law, Su Yunrui.Their family is so poor they can barely make ends meet.Then suddenly, his beautiful wife comes smiling, bringing him a bowl of hot porridge.“Husband, I was wrong yesterday. Please have some porridge while it's hot.”Seeing the bruises on his wife's face, Chen Jie feels something is amiss.Ding~[Daily Information has been updated][1. Yesterday, you gambled away the last three acres of good land, beat Su Yunjin while drunk, and planned to sell the five-year-old Su Yunrui, to recover your losses.][2. The Su sisters rely on each other. Su Yunrui is Su Yunjin's only hope.][3. Su Yunjin, having lost hope, traded her mother's hairpin three days ago for a pack of arsenic.]...Arsenic!Staring at the hot porridge brought to his lips, Chen Jie looks up at his wife, seeing the faint bruise on her face and her eyes shifting away, avoiding his gaze.“Honey!”“Yes?”“You're not going to kill me, are you?!”

Short Version:An overpowered man helps anime and comic characters in exchange for sex.Long version:In an unexpected turn of events, an average man meets his demise and finds himself transported to a mysterious new world. Driven by his deepest desires, he yearns to create a group of women who adore him—a Harem. However, he soon discovers a surprising truth: there are no women in this world.Determined to escape this peculiar realm and protect his virtue, our hero sets out on a challenging journey of self-improvement. Through hard work and unwavering commitment, he attains godlike powers. But even with his newfound abilities, he finds himself confined to a shop within the vast multiverse.Within the walls of this enigmatic shop, our protagonist faces his true test. As a divine duty, he must assist distressed women from different parts of the multiverse, offering them his strength and guidance. However, the cosmic balance demands a price, and the reward he gets is.... SexThroughout his adventure, our hero encounters women from various backgrounds, each with their own unique struggles and stories. As he ventures forth, he becomes deeply involved in their challenges, providing comfort, advice, and protection.Yet, amid his selfless acts, the man secretly hopes that someday, somehow, his unwavering dedication and kindness will be reciprocated. Will his cherished dream of a Harem come to fruition, or will the universe have different plans for him?Embark on this captivating journey, where desire, determination, and duty intertwine, showcasing a man's quest for personal fulfillment and the salvation of others......Worlds:Oshi no koChainsaw manMarvelDCOne pieceNarutoAttack on titanBleachJujutsu KaisenOne punch manAnd more....