One Piece : Start As Celestial Dragon And Take Down Hancock - Chapter 134: Arrival at Sabaody Archipelago. (R-18)

Due to a problem in his soul, Rean never cared about anything in his life. Even though he died heroically, there wasn’t really a 'will' behind that action.

It has been a year since Li Fuchen lost his “talent”. Now he lives the life of a wastrel, being bullied and beaten by those who were once inferior to him. However, he has still not lost everything as he is engaged to a strong and pretty girl of a powerful family… but that came to an end as the engagement was abruptly anulled. With shame brought to the family and his life engulfed by darkness, a ray of hope pierced through the sky.

Before going to college, an ordinary high school student went to celebrate and got drunk. When he woke up, he found himself in a completely different world. There was a big sect, the approaching sect entrance examination, a slum where his body’s previous owner lived, and a shared memory about a missing young girl.

When he got tangled in a fight with a few punks in this different world, he fell off a cliff and miraculously found himself still alive, with two more voices ringing inside his head. They were Sword Master and Saber Master. In the company of them, he continued to find out more about this whole new world. He took the sect entrance examination, entered the sect, met a strange man in black, and even participated in a major competition of the sect to have a chance to win over his peers!
In this whole new world, he was born again and got to explore the fantastic martial world!

- Description from Novelupdates

He is the ruler of the mercenary realm, an overlord that gives headaches to the leaders of any country! For the sake of his friends, he’s willing to sacrifice himself; for the sake of his family, he does not hesitate to spill blood! He is a dragon, one that soars above even the highest of heavens. He’s a power that advances triumphantly through unstable situations, stirring up both the winds and the waters.

- Description from Novelupdates