Koko wa Ore ni Makasete Saki ni Ike to Itte kara 10 Nen ga Tattara Densetsu ni Natteita - Chapter 281 - – Thrall and Human

Merged into the body of External Disciple Chen Yu was the heart of a demonic god.The heart is the core of life, the most fragile vital organ. To Chen Yu, however, the heart was his greatest strength, granting him power and potential beyond demonic and divine beasts. Here on out, we follow him as he embarks on a mysterious and wonderful journey.

Death is sometimes not the end!
Dead prison!
This is a magical prison. It has the ability to draw the souls of the dead people of the world, and it also enables people to gain the ability of the souls of the dead.
When Qin Song woke up, he was shocked to find that he had come to the world of One Piece, and even more surprised that he found a prison in his body…..

- Description from Uukanshu

Six years ago, he disappeared silently! After six years, he becomes the unparalleled "God of War" and returns with glory, only to find that he has a daughter whom he never knew of. Looking at his wife and his daughter, he says, "In this lifetime, I'll bring you the greatest honor and glory!”

«Bleh.» — Imp. An Imp, a monster known to kill with a grin, a demon of the world, a creature of incredible might! Something that no force in the world can stand against! At least that’s what the Main Character would like himself to be, the reality is very different, however.

Exactly that Imp stumbles along a path of unfortunate fortunes and grows through it, in a world that hates its very existence.

It grows more intelligent, more powerful, simply better at whatever it needs to do. Amongst other things, that includes raising children, killing Soldiers, and carving wooden figurines for money.