MTL - Poison Doctor Demon Consort - Chapter 63 , Bai Dijian, Tenglong thirteen

Ron finds himself reborn in the world of One Piece, stranded on a remote island in the East Blue. But he's not just any ordinary child—he’s bonded to a mysterious sign-in system that grants him powers with every new location he visits.At his first sign-in, he unlocks the legendary Sun Breathing Technique, along with a boost to his vitality. From Shitmotsuki Village to Skypiea, Enies Lobby to Marineford, Ron travels the world, collecting extraordinary rewards that make him a force to be reckoned with. The Raikiri, one of the 21 Great Grade Swords, Armament Haki, Observation Haki, and more fall into his hands.As Ron steps onto the battlefield of Marineford during the legendary Summit War, the mightiest warriors—Four Emperors and Marine Admirals alike—pause, stunned by his presence. But Ron merely waves them off, “Don’t mind me. I’m just passing through.”Join Ron on his journey across the Grand Line as he signs in at iconic locations, growing stronger with every step. This is not just an adventure—it’s a legend in the making.

At first, when he learned that he was forced to go to many different routine worlds and be reborn into all kinds of cannon fodder, he was against it.

There’s an ancient saying in Great Ruins, ‘Don’t go outside when it’s dark.’

In Great Ruins, the disabled elders of Disabled Elderly Village picked up an infant by the riverside and named him Qin Mu, raising him up with blood and sweat. This day, as the night descended and the darkness shrouded Great Ruins, Qin Mu left home…

Become a villain undulating in the spring breeze!

That’s what Blind told him.

This is the rise of Qin Mu’s road to becoming a villain!

- Description from novelupdates

A 13-year-old deaf teenager living in the 21st century suddenly found himself as a young boy in Japan during the early 1900s. With two World Wars, two nuclear bombs, Hitler and many other disasters awaiting his future, he thought things couldn't get worse.Except it did.He found out later on that he had actually reincarnated into the world of Demon Slayer where man-eating demons ruled the night. He thought things couldn't get worse.Except it did.But hey! At least he had unparalleled talent, incredibly special eyes and future knowledge.How will the story of Demon Slayer change with the addition of this unique character? Will so many still die if the Hashiras had one more pillar in the final battle?Or will the story end on a much happier note?