It is the early 21st century, and mankind is doomed. Due to a mysterious virus that steals the essence of human life, humanity has been pushed to the brink of extinction with only one hope for salvation: the blood of a vampire. Vampires have closely guarded the key to curing the virus for several years, which has led to an immense rift between them and humans and the world's descension into chaos. A vampire named Duo, having leaked the secret to saving humanity, is now considered a traitor to his race, and the powerful vampire Zieg is on his trail. However, due to Zieg's sense of duty, his heart is torn: should he kill the man who betrayed his people, or will his personal history with Duo sway him to have a change of heart?

In a small village, twins are born: a boy, Tatara, and a girl, Sarasa. The prophet Nagi declares that Tatara is the chosen one who will free Japan from the tyrannical rule of the King and his four sons. But when the ruthless Red King slays Tatara, Sarasa must take on her brother's name and responsibilities and embark on a quest to free Japan and deliver vengeance to the Red King. (Source: ANN)

The story continues after the intraschool music competition of the first game and anime series. The budding music student Kahoko meets the brusque boy Etō, the new youthful school board director Akihiko Kira, and the mysterious transfer student Aoi Kaji. (Source: ANN)

Lord Haven watches over a secluded village in the realm of Djana En. Redon, his son, feels unsatisfied with his tranquil yet dull life of assisting the townsfolk in their labor. When his parents are suddenly assassinated, Redon must flee the village with a handful of companions. As the group is cornered at the edge of God's Wall, the mystical snakeskin that seals off Djana En from the rest of the world, a voice beckons to Redon. It urges him to enter a fresh opening in the wall and travel to the fabled land of Crystania, where he can obtain incredible power. Without any other options, Redon and his comrades escape through the mysterious passage, only to find a Crystania far different than how the legends picture it. Faced with danger and shape-shifting beastmen, Redon and his party wonder if they stumbled into someplace worse than where they came from. Things take a favorable turn, however, when the group meets a pair of travelers knowledgeable about the tumultuous state of Crystania.