Flowers Are Bait - Chapter 155:

Soul System Online...][Vengeful Spirit Detected]Zero was once a legend a warrior feared and respected across the land, an SSS-ranked hero at the peak of power. But even the strongest are not immune to betrayal. His so-called allies turned against him, casting him into oblivion. Now, he lingers as a vengeful spirit, unable to move on, his legend seemingly forgotten.But fate isn’t done with him yet.When a mysterious boy with the rare ability to see and communicate with spirits crosses his path, Zero sees a chance for revenge and maybe even redemption. Armed with the enigmatic Soul System, he will carve a new path, defying death itself.The world thinks it has seen the last of him. They couldn’t be more wrong.The SSS-Ranked Troublemaker has returned. And this time, nothing will stop him.

Pirate World, Before the Summit War.Sengoku: “In this war, the advantage is ours!”Vice Admiral Tsuru: “Can we really win?”Sengoku: “We will win.”As the Summit War begins, chaos erupts on the battlefield.Above Marineford.Suddenly, Will appears in the sky with his crew, overlooking the entire battlefield.Sengoku: “What exactly are you here for? Are you planning to help Whitebeard?”“Don’t misunderstand.”Will scans the battlefield, his gaze sweeping over the powerful figures present. A hint of excitement lingers in his tone.“I’m only here for one reason—to kill all of you. That’s it.”Sabaody Archipelago.Will watches the Celestial Dragons strutting arrogantly through the streets, their eyes filled with disdain for the world. He can’t help but frown.“These are no ordinary Celestial Dragons… This calls for a heavy punch!”...Without hesitation, he throws a devastating punch, obliterating a Celestial Dragon on the spot, crushing the surrounding Marines and CP agents with overwhelming force.The survivors turn to a trembling communications officer clutching a Den Den Mushi and scream in terror:“Hurry! Notify Marine Headquarters! Call for an Admiral!”

Another entry in what you can call the Proto Harem Series: the books written before the Harem Series that take place in the same world.

It’s about a swordswoman whose student is captured, so she goes to rescue her.

The world had started doomsday, and I struggled for a year, before I died under an enchanted beast’s claw. Heaven has given me another chance, back a day before the end happen. Will I be able to change my fate, and that of my loved ones? Now, I will start my journey on becoming the strongest on the planet that the Gods have changed into a game world.