Phantom Pain
The story takes place around three months after the JS Incident came to an end.
Ginga, who wants to let Vivio and the Reformed Numbers see each other, and Nanoha, who refuses to let that happen. As the reasons and circumstances they each have, which don't let them cede ground, come to light, so, too, does the mystery reveal itself.
Even if the incident has come to an end, the "pain" hasn't.
...And, well, though I was aiming for a serious/heart-warming story, for some reason, it ended up having slight touches of mystery in it, too. It's the kind of story that makes you think "Why is she lying?" and "Who's actually the crying kid?"
This is a 40-page-long manga filled with story.