Several months have passed since the Jewel Seed incident, and Nanoha Takamachi is getting ready to welcome Fate Testarossa back from her trial with the Administrative Bureau. Having received conditional clemency for her role in preventing the crisis, Fate has been allowed to attend school with Nanoha. However, before the two girls can settle into their daily lives together, a group of dark mages suddenly descend upon them. Overpowered by their unknown assailants, Nanoha and Fate have their mana absorbed by an ominous grimoire, and both Raising Heart and Bardiche are damaged in the process. The ones behind this ambush are known as the Wolkenritter, and its four members—Vita, Signum, Shamal, and the familiar Zafila—were summoned by the Book of Darkness to carry out its malignant bidding. The book's current owner is the young girl Hayate Yagami, oblivious to its true nature while the Wolkenritter, charging its power with the forcibly stolen mana, is duty-bound to seek the tome's completion. Left drained and weaponless, Nanoha and Fate must race against time to recover their strength and confront the Wolkenritter, with the aim of preventing the quartet from finishing the Book of Darkness and unleashing its devastating magic upon the world.

In the harsh region known as the borderlands, humans must fight an endless battle against demi-human creatures that come at them relentlessly, intent on taking their land and their gods. A young boy named Kai, fighting to defend his village, sustains a life-threatening injury that causes him to regain memories from a past life. If you're not a guardian bearer, it's like you're playing life on hard mode... Kai's newfound knowledge gives him a new sense of the unfair rule set that governs the world around him. One thing is clear: For those without a god to serve as their guardian, life is a constant struggle for survival. Thus begins the epic tale of a young boy's ascent into a vast world filled with magic, bloodshed, and mystery. (Source: J-Novel Club)

Vivio Takamachi, a Sankt Kaiser royalty of ancient Belka, was previously subjected to mistreatment. Fortunately, she now lives a peaceful life with family and friends while practicing martial arts with her coach, Nove Nakajima. However, Vivio soon becomes the target of the mysterious fighter Heidi E. S. Ingvalt, who demands Nove to reveal the location of the ancient Belkan royals. Refusing to disclose this information, Nove finds herself in a losing battle but Heidi soon falls unconscious. In addition, Nove discovers Heidi's true identity to be a middle school student named Einhald Stratos. When she regains consciousness, Einhald clarifies that she has no animosity toward ancient Belkan royals. Having inherited the passion to defend and harboring regretful memories of her ancestor, the ancient Belkan ruler Claus Ingvalt, she simply wants to prove that her fighting ability is strong enough to protect others. Intrigued by the girl's situation, Nove arranges for Einhald to meet with Vivio. Although they get off to an unconventional start, Vivio enthusiastically trains with Einhald, assisting her in finding peace of mind while developing a vivid friendship along the way.

With the arrival of a new generation of talented girls, another lively year at Seishou Music Academy begins. The graduating 99th class is already preparing for the much-anticipated rendition of Starlight, a bittersweet story about the parting of two girls. It seems like all students in the Actor Training Department have their post-graduation future figured out—except for the cheerful Karen Aijou. Having fulfilled her promise of performing in a play with Hikari Kagura, her ambitious childhood friend, Karen struggles to find her purpose. What lies beyond their promise is a mystery to Karen, as Hikari was the fuel that kept her passion for performing aflame. Now alone, Karen must confront the reality of stage girls and find her way toward the future—her very own stage.