Itai no wa Iya nanode Bōgyo-Ryoku ni Kyokufuri Shitai to Omoimasu - Chapter 345

There was a man in the modern world that built his business empire from scratch. He was hailed as a genius by his peers and was respected worldwide due to his contributions to the world.If it is not only for that unfortunate accident that led to his death. He was a man who could potentially change the world with his mind that still stores a plethora of ideas.But—fate had others plan with him. He found himself in another world, what’s more, it’s primitive and technologically backwards compared to his last world. And what’s more, he turned into his younger self, and in this world, he was an orphaned boy.For him to survive, he must use everything that he had at his disposal, and that was all in his head.

Cao Xin, a young man on earth, died in a car accident, traveled to a troubled world where supplies were scarce, and obtained a “Bronze Immortal Gate”…

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- Description from novelbuddy

On his 32nd birthday, Jeff, along with all of his friends, confesses how they are dissatisfied with their lives.If only I didn't suppress my desires.If only I didn't ignore my feelings for her.If only I confess my love to her.If only I had chosen a different path from the start.If only...At the end of his 32nd birthday, the next morning, Jeff wakes up a decade back to the past. And as if all of his friends have trusted all of their regrets to him, Jeff remembers them all.With his regression that gave him a mysterious system known as Returner Fantasy, Jeff will do everything to change the future, not only for himself but for his friends and the ones he loves.[Warning: Contains Mature and Sexual content.]This book will have a lot of mature and sexual content. But those will not be the main focus of story.This book will show characters trying their best to redeem themselves from their failures and regrets.