These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Blood That Flows
A Fate Worse Than Death: From Signum's point of view, Cinque may have inflicted this on her if she's unable to fight again for the rest of her life due to her injuries.
Reinforce suffers it as well, as Levi violates her body, mind-wipes her, and sics her on Hayate. The ensuing fight ends with the nearly-dead soulless killing machine that was once Reinforce being permanently Unison-fused with Hayate, essentially ceasing to exist.
Archive Panic: 200+ chapters and 400,000+ words and still no signs of stopping.
The author has stated that he has plans to go all the way through NanohaForce.
Complete Monster: Death Bringer Garoth, one of the Mazoku lords under Chaotic Blue. He's responsible for the destruction of Al-Hazard, the corruption of the Book of Darkness, the chaos that engulfed Saint Kaiser Olivie's reign as well as her death, the disruption of Precia's experiment and the corruption of Alicia into Levi (who is a black-hearted monster in her own right thanks to his influence), and possibly more heinous acts.
Alicia, later named Levi, does horrible things to Lutecia and Reinforce, quickly putting her into this category.
Hilarious in Hindsight: In the Peek arc, it is revealed at least in this story that Reinforce Eins is a human turned into a Unison Device. With the release of Magical Girl Lyrical Nanoha A's Portable, it is revealed that the Unbreakable Darkness, aka the Darkness of the Book of Darkness, was a human that got turned into a Device.
In the Revolution arc Corona gets a ton of pure Black Magic poured into her Linker Core, causing her to undergo a massive change in personality, in the 2nd movie, guess what happened to Hayate thanks to the Protection Program?
Speaking of the second movie, in the A's arc of this fic, the Protection Program fought back against everyone before being taken down, and, yes, it happened in the movie as well.
Sticking to the 2nd movie, in Blood That Flows, it's revealed that Reinforce had a device in the past. In the movie she has Nachtwal.
Lutecia falls into this category. Her body's been modified so that she's physically older, has become completely subservient to Levi, and she's been sexually molested and taken advantage of by Levi several times.