Hortensia Saga is a medieval fantasy tale of war and chaos. Three years ago, the king was betrayed and murdered by one of his dukes who then rebuilt the kingdom into his own. But now, the original heir to the throne has secretly come of age. Hiding in the guise of a man, she and her loyal band begin the quest to save her homeland. (Source: Kotaku, edited)

Mirai Kuriyama is the sole survivor of a clan of Spirit World warriors with the power to employ their blood as weapons. As such, Mirai is tasked with hunting down and killing "youmu"—creatures said to be the manifestation of negative human emotions. One day, while deep in thought on the school roof, Mirai comes across Akihito Kanbara, a rare half-breed of youmu in human form. In a panicked state, she plunges her blood saber into him only to realize that he's an immortal being. From then on, the two form an impromptu friendship that revolves around Mirai constantly trying to kill Akihito, in an effort to boost her own wavering confidence as a Spirit World warrior. Eventually, Akihito also manages to convince her to join the Literary Club, which houses two other powerful Spirit World warriors, Hiroomi and Mitsuki Nase. As the group's bond strengthens, however, so does the tenacity of the youmu around them. Their misadventures will soon turn into a fight for survival as the inevitable release of the most powerful youmu, Beyond the Boundary, approaches. [Written by MAL Rewrite]

"With the help of the "Dragon Sin of Wrath" Meliodas and the worst rebels in history, the Seven Deadly Sins, the "Holy War", in which four races, including Humans, Goddesses, Fairies and Giants fought against the Demons, is finally over. At the cost of the "Lion Sin of Pride" Escanor's life, the Demon King was defeated and the world regained peace. After that, each of the Sins take their own path; the first being the "Boar Sin of Gluttony" Merlin, who works together with King Arthur aiming to create a new kingdom." "Meliodas was traveling with Princess Elizabeth to a place of memories. Along the way, by chance he reunites with his younger brother, Zeldris. Meanwhile, the wedding of Harlequin, the "Bear Sin of Sloth", and Diane, the "Serpent Sin of Envy", was about to take place, at a blessed ceremonial hall, with the presence of the "Fox Sin of Greed" Ban and the "Goat Sin of Lust" Gowther as well. With the advent of Diane in a dress, an eerie sound like the rumbling of the earth began to echo in the brilliant forest." "Punish the Seven Deadly Sins that ruined the Holy War and those who contributed to it." "Suddenly, an army of Fairies and Giants rushes to the land where peace should have come. Leading the enemy are the once missing "Second Fairy King" Dahlia and the "Giant Master Craftsman" Dubs. What is the purpose of the strange-eyed invaders...?" "Everyday life is destroyed by those who desire the chaos of the world. A terrifying conspiracy that threatens all races develops. What is the future ahead of the battle between light and darkness?! Can this cursed world have true peace? The fate of the fragile world is entrusted again to the reunited Seven Deadly Sins."

The story follows Iruma Suzuki, a 14-year-old human boy, who is sold to a demon by his parents. The demon, known as Sullivan, takes Iruma to the Demon World and officially adopts him as his grandson. He enrolls Iruma in the Babyls School for Demons where he is the headmaster and where Iruma quickly befriends the demons Alice Asmodeus and Clara Valac. However, Sullivan tells Iruma to never reveal that he is human since he will be eaten if anyone finds out. Iruma then vows to blend in during his time in the demon world, although he only stands out because of all the situations and adventures that arise.