Rebirth in One Piece as Deputy Captain - Chapter 583

A teenager who unexpectedly gets transported to the modern world from ‘the world of the immortals’ . He finds himself in the body of an ordinary guy. He wants to go back to his world and for that, he will have to practice to get stronger and investigate the reason why and how he crossed through to this world.

- Description from Novelupdates

Corporate slave Alexander dies with only one regret—not finishing the fantasy novel in his hands. Fate has a twisted sense of humor when he awakens as Alexander Flamingo, the perverted villain destined to be expelled and killed in that very story!Armed with complete knowledge of the original plot and a mischievous “Harem King System,” Alexander plans to rewrite his fate. No longer the one-dimensional pervert of the novel, he'll use his future knowledge to manipulate heroes, seduce heroines, and rise from disposable villain to the true mastermind of this world.The system grants him power through every relationship he builds—but can this calculating reincarnator use his second chance to avoid his predetermined death and become the ultimate Harem King? One thing's certain: this story won't follow the original script.

Born into a dirt poor mining family, Karl only had one chance to get ahead in life, the annual elite recruitment day. On their final day of middle school, every student in the Golden Dragon Nation was given an experimental injection to awaken their affinity with magic.

Those few who succeeded would become the Elite, the leaders and idols of the nation, blessed with incredible magical powers and respected by all. Those who did not would return to their normal lives of hard work and low wages, just doing the best they could.

But with the nation surrounded by enemies, both humans and monsters, how long would these peaceful days of magical idols last?

Follow the story of Karl as he awakens a unique power and strives to become the world's first Legendary Beast Master.