Barely surviving in a barrel after passing through a terrible whirlpool at sea, carefree Monkey D. Luffy ends up aboard a ship under attack by fearsome pirates. Despite being a naive-looking teenager, he is not to be underestimated. Unmatched in battle, Luffy is a pirate himself who resolutely pursues the coveted One Piece treasure and the King of the Pirates title that comes with it. The late King of the Pirates, Gol D. Roger, stirred up the world before his death by disclosing the whereabouts of his hoard of riches and daring everyone to obtain it. Ever since then, countless powerful pirates have sailed dangerous seas for the prized One Piece only to never return. Although Luffy lacks a crew and a proper ship, he is endowed with a superhuman ability and an unbreakable spirit that make him not only a formidable adversary but also an inspiration to many. As he faces numerous challenges with a big smile on his face, Luffy gathers one-of-a-kind companions to join him in his ambitious endeavor, together embracing perils and wonders on their once-in-a-lifetime adventure.

The Four Cardinal Heroes are a group of ordinary men from modern-day Japan summoned to the kingdom of Melromarc to become its saviors. Melromarc is a country plagued by the Waves of Catastrophe that have repeatedly ravaged the land and brought disaster to its citizens for centuries. The four heroes are respectively bestowed a sword, spear, bow, and shield to vanquish these Waves. Naofumi Iwatani, an otaku, becomes cursed with the fate of being the Shield Hero. Armed with only a measly shield, Naofumi is belittled and ridiculed by his fellow heroes and the kingdom's people due to his weak offensive capabilities and lackluster personality. When the heroes are provided with resources and comrades to train with, Naofumi sets out with the only person willing to train alongside him, Malty Melromarc. He is soon betrayed by her, however, and becomes falsely accused of taking advantage of her. Naofumi then becomes heavily discriminated against and hated by the people of Melromarc for something he didn't do. With a raging storm of hurt and mistrust in his heart, Naofumi begins his journey of strengthening himself and his reputation. Further along however, the difficulty of being on his own sets in, so Naofumi buys a demi-human slave on the verge of death named Raphtalia to accompany him on his travels. As the Waves approach the kingdom, Naofumi and Raphtalia must fight for the survival of the kingdom and protect the people of Melromarc from their ill-fated future.

Unlike many schools, attending Hyakkaou Private Academy prepares students for their time in the real world. Since many of the students are the children of the richest people in the world, the academy has its quirks that separate it from all the others. By day, it is a normal school, educating its pupils in history, languages, and the like. But at night, it turns into a gambling den, educating them in the art of dealing with money and manipulating people. Money is power; those who come out on top in the games stand at the top of the school. Yumeko Jabami, a seemingly naive and beautiful transfer student, is ready to try her hand at Hyakkaou's special curriculum. Unlike the rest, she doesn't play to win, but for the thrill of the gamble, and her borderline insane way of gambling might just bring too many new cards to the table.

Young Thorfinn grew up listening to the stories of old sailors that had traveled the ocean and reached the place of legend, Vinland. It's said to be warm and fertile, a place where there would be no need for fighting—not at all like the frozen village in Iceland where he was born, and certainly not like his current life as a mercenary. War is his home now. Though his father once told him, You have no enemies, nobody does. There is nobody who it's okay to hurt, as he grew, Thorfinn knew that nothing was further from the truth. The war between England and the Danes grows worse with each passing year. Death has become commonplace, and the viking mercenaries are loving every moment of it. Allying with either side will cause a massive swing in the balance of power, and the vikings are happy to make names for themselves and take any spoils they earn along the way. Among the chaos, Thorfinn must take his revenge and kill Askeladd, the man who murdered his father. The only paradise for the vikings, it seems, is the era of war and death that rages on.