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.

Fourteen-year-old Iruma Suzuki has been unfortunate all his life, having to work to earn money for his irresponsible parents despite being underage. One day, he finds out that his parents sold him to the demon Sullivan. However, Iruma's worries about what will become of him are soon relieved, for Sullivan merely wants a grandchild, pampering him and making him attend the demon school Babyls. At first, Iruma tries to keep a low profile in fear of his peers discovering that he is human. Unfortunately, this ends up being more difficult than he expected. It turns out that Sullivan himself is the chairman of the school, and everyone expects him to become the next Demon King! Iruma immediately finds himself in an outrageous situation when he has to chant a forbidden spell in front of the entire school. With this, Iruma instantly earns a reputation he does not want. Even so, he is bound to be roped into more bizarre circumstances.

Hikari Hanazono has always been able to do things that normal people cannot. As a child, she assumed no one could beat her—until she met Kei Takishima. Thinking she would win, Hikari challenged him to a match. But things didn’t go as planned; she lost not once but each time she rechallenged him. From that point on, she has sworn to best Kei at everything, ranging from academics to athletics. To achieve her goal, Hikari enrolls in the same school as Kei—Hakusenkan, a prestigious institute for the wealthy. As a pair, they hold the top two rankings in school and are among seven of the academy's best students in a class known as Special A. While Hikari treats Kei as a rival, she is completely oblivious that he harbors hidden feelings for her. Together, the members of Special A deal with competition, friendship, and just a bit of love.

After many trials and tribulations, Iruma Suzuki is finally happily living among demons despite having to hide his true identity as a human. Even more so, he has now found his ambition in life: keep ranking up in this world! However, that plan is halted when Iruma's club is temporarily dismissed, and he is forced to be part of the student council, known for its strictness toward rowdy students. Its cold-hearted president is Amelie Azazel, Iruma's friend. Although Iruma is not used to following their rigid schedule and many rules, he still wants to prove himself and help Amelie alongside all of the other members of the council. But trouble arises when Amelie's personality completely changes due to strange circumstances, putting the student council's reputation in jeopardy. Will Iruma be able to save them and avoid having the whole school turn into pure chaos?