Maintaining a delicate balance of power, the kingdoms of Amoria, Ishilfen, and Vanrodis rule over the continent of Kuna'anh. Even the slightest hint of trouble in one country could spark a continent-wide war. However, their one common fear is the evil dragon Daganzord, whose only meaning of existence is to devour and destroy all life. Ten years ago, a group of mages worked together in an effort to seal away the malevolent beast. But the ritual—later known as the Balbagoa Tragedy—was a failure, and many lost their lives. Though his parents died in this tragedy, Hiiro was saved by the swordsman Giruu. Under the latter's tutelage, Hiiro learned swordsmanship with the sole purpose of seeking revenge. Now a budding master himself, he sets out in search of Daganzord in order to realize his long-awaited vengeance, or to be consumed by the dragon and meet the same fate as his parents.

When 20-year-old college student Haruto Amakawa dies in a traffic accident, he does not expect to wake up in an unfamiliar world in the body of a young boy named Rio. As their memories and personas fuse, Rio realizes that he now also possesses magical powers. He is relieved to find that his burning passion for revenge against his mother's murderers has not subsided, despite his newly changed identity. Not soon after, Rio comes across the kidnapped princess of the Bertram Kingdom and saves her without hesitation. To express his gratitude, the king grants him the opportunity to enroll in the Bertram Royal Academy. Believing this to be a new chapter in his life, he is excited to study at this prestigious academy, but life here proves to be difficult for him, a slum-dweller surrounded by the majestic children of nobles.

The sole surviving human and her canine companion, Haru, wander a desolate wasteland after the destruction of civilization, but this is no dark doomsday tale. Haru, a wise-beyond-his-years talking shiba inu, makes sure his master stays one step ahead of post-apocalyptic pessimism with his clever antics, hilarious observations and philosophical ponderings. She may be the last girl on earth, but with Haru at her side, the road through the apocalypse will never be boring! (Source: Sentai Filmworks)

Each episode tells a different story from Grimm's Fairy Tales.