God Emperor - Chapter 7: Sacred Sword Skill

He died on the wedding of the girl he had a crush on, after a long and successful career. After convincing Yama to send him back to the world, he decides to fix the areas in which his life went wrong. Realizing the lack of love and romance in his past life, he sets out to conquer the hearts of various women.

Travel to the world of One Piece?

They come, the security;

Became Don Quixote Rossindi?

Forget it, it can’t be reopened;

But after realizing that he had eaten the fruit of silence, the little boy became restless.

Fruit of Silence, this is one of the devil fruits that can compete for the title of “the most useless” in the world of One Piece; it is only a little better than Chopper’s “Everyone’s Fruit · Common People’s Form”!

“Dover, you said you are a devil fruit wholesaler, why do your family eat all kinds of weird ones?”

Facing the bewildered little Dover, Rossindi patted his forehead.

“Forget it, let’s practice domineering hard.”

- Description from novelbuddy

Amakawa Haruto died before he’d the chance to reunite with his childhood friend who disappeared five years ago. Rio, a young boy living in the slums seeks revenge for his mother who was murdered in cold blood in front of him when he was only five years of age.

There exists the earth many knows of and there exists an alternate world. Two people, each with their own backgrounds and values. For odd reasons, the memories and personality of Haruto, one who should have died resurrects in Rio’s body. As the two are confused over their memories and personality fusing together, Rio (Haruto) decides to live in this new world.

Along with Haruto’s memories, Rio awakens an unknown but special power. If he’s to use it, it looks as if he can live a better life, but before that, Rio encountered a kidnapping which results in involving the two princesses of the Bertam Kingdom.

After saving the princesses, Rio is given a scholarship to attend the Royal Academy, a school for the rich and powerful. His background being a poor orphan who once lived in the slums, the school full of nobles was rather a detestable place to stay at.