Following Armageddon, an apocalyptic war, mankind faces yet another menace: vampires. The continuous confrontations between the races have split the world into separate factions. The race of vampires, Methuselah, are affiliated with the New Human Empire; whereas the humans, deemed Terrans by the vampires, make up the Vatican Papal State. Furthermore, extremist groups like the Rosenkreuz Order strive to rekindle a war, despite the factions' attempts to avoid direct conflict. To combat terrorist organizations, the Vatican has implemented the AX unit. Led by Cardinal Caterina Sforza, the AX agents investigate vampire-related disturbances with hopes that the Terrans and the Methuselah will one day achieve peaceful coexistence. Amongst the AX unit is priest Abel Nightroad—a seemingly disoriented but gentle-hearted fellow who is a fierce vampire slayer on the battlefield. Joining the unit as his partner is agent Sister Esther Blanchett, a brave and gentle young nun troubled with a tragic past. As the two grow closer, they begin to uncover signs of malicious schemes and dark forces working in the shadows. But the path they walk is riddled with misfortune that might just force them to confront the memories that plague their hearts.

Shinichi Chiaki is quickly making a name for himself as the principal conductor of the revitalized Roux-Marlet Orchestra, and Megumi Nodame Noda has made leaps and bounds as a pianist at the Conservatoire de Paris. However, tensions mount between the two as Nodame feels left behind by Chiaki's growing success and his close friendship with legendary piano prodigy Rui Son. Disregarding her teacher Professor Charles Auclair's advice, Nodame enters another piano competition in an attempt to jumpstart her own performance career. Meanwhile, those around Chiaki and Nodame are at their own crossroads. Rui begins to doubt herself after hearing Nodame's playing and being denied tutelage from Auclair; Maestro Franz von Stresemann faces the reality of his mortality; pianists Yunlong Li and Tatiana Vishneva feverishly prepare for a competition, while the latter also struggles with her growing feelings for oboist and fellow student Yasunori Kuroki. As Chiaki, Nodame, and their friends continue on their respective journeys, they must not only strive to stay true to themselves, but also remember where it all started.

Just as the famous writer Sensei is about to accomplish his life ambition and commit double suicide with his lover Sacchan, he is hit by a truck and transported to another world. Deemed an adventurer by the local priestess Annette, Sensei is given the daunting mission of slaying the demon king. Refusing to play into his new role, Sensei decides his efforts are better served looking for Sacchan in the hope that she is somewhere in this new world. Early on in his journey, Sensei crosses paths with the martial artist Tama and unexpectedly saves her from mortal peril. Grateful for his actions, Tama decides to escort him. The pair are soon joined by Annette who, seduced by the writer's strong personality, has sworn to protect Sensei's life. As the unlikely trio wander the dangerous, monster-infested lands, they soon realize that human beings might be the true threats to the peace of the world—and Sensei might be the only one with the power to stop them.

An injured man is found in the woods by a girl named Eruruu, and everything about him is mysterious. Without knowledge of his past nor even his own name, he is welcomed to Eruruu's home and is given the name Hakuoro by her grandmother, and younger sister, Aruruu. While the inhabitants of the village have large ears and tails, Hakuoro's defining physical trait is quite different as he has neither ears nor tail, but only a mask that he cannot remove. Soon after he becomes a part of the villagers' lives, a revolution against the tyrannical emperor of the land begins, and the conflict finds its way to his new home. Hakuoro must do whatever he can to save the people and the village that he has come to love, all while uncovering the mysteries that shroud his past.