After solving the incident of the scattered Jewel Seeds, Nanoha Takamachi happily returns to her everyday life, though now with added magic practice in the morning. Exchanging video messages with Fate Testarossa and the crew of the Arthra, Nanoha eagerly awaits the chance to speak with them in person again. But while studying in her room one day, Raising Heart suddenly calls out to Nanoha and warns her of an incoming attack! The attacker is a young girl named Vita, who calls herself a Belka Knight. She proves her strength by using an intelligent device with a mysterious cartridge system to quickly overwhelm Nanoha. Luckily, the Space-Time Administration Bureau is able to step in before she is completely crushed. Vita and her fellow knights Shamal, Signum, and Zafila are on a mission to steal magical power from mages in order to complete the Book of Darkness, one of the Lost Logia. For what sinister purpose are the knights after this Book of Darkness? [Written by MAL Rewrite]

Not all is normal in Tomobiki, even by its standards. The students have been preparing feverishly for the first day of the student fair, which is scheduled to go on the next day. However, problems arise when some begin to notice that the next day simply will not come. As the students begin to try to find the reason for the problem, their beliefs about reality and the world of dreams are challenged.

Thousands of years ago, the ancient dragon Bahamut wrought havoc upon the land of Mistarcia, a world where both gods and demons live amongst mankind. Working together to prevent the world's destruction, the rival deities barely managed to seal Bahamut, agreeing to split the key between them so that the dragon would remain eternally imprisoned. With the world safe from the destruction of Bahamut, it is business as usual for bounty hunters like Favaro Leone. Living a laid-back, self-serving lifestyle, the amoral Favaro goes about his work while on the run from fellow bounty hunter Kaisar Lidfard, a righteous man who swears vengeance upon Favaro. However, Favaro's carefree life is thrown into chaos when he meets Amira, a mysterious woman who holds half of the key to the world's fragile peace. Shingeki no Bahamut: Genesis tells the story of a group of unlikely heroes who find themselves caught in the middle of an epic clash between gods and demons, forced to carve their own path in the face of the imminent storm.

One year after goddess Belldandy emerged from Keiichi Morisato's mirror and promised to stay with him forever, a new threat to their happiness emerges, one that could end the contract between Belldandy and Keiichi.