Roon x Nero (kinda) (no cringy sex ahead)

Prelude

There's barely any light: the only light sources are the hundreds of thousands of screens placed onto the apparently neverending walls; but even though there are many, they do not illuminate much. Each screen is displaying something different from the other: some are showing daily life scenarios at the Azur Lane HQ, others are displaying major or minor battles fought between the Azur Lane and the Crimson Axis or between the Azur Lane and the Sirens, others are just static, others are showing graphs and charts containing numerous data. This space seems infinite, as though the very concept of space doesn't exist in this environment. Surrounded by all these screens is a petite girl: from a distance, one could say she is a little girl like any other, but as we draw nearer we realize that is not a kid at all. She sits back on one of her cannons as her bright yellow eyes wander up and down, left and right, while they keep up with the massive amount of information displayed on the screens. Some of the footages amuse her, others don't get any particular reaction from her, the graphs and charts are studied and analyzed by her superhuman brain and memorized in an instant. This girl, whom we know as Observer Alpha, spends most of her day like this. It is her favorite activity: watching the events occurring in various timelines in real time.

"I don't think I'll ever understand how you find this entertaining." An acute feminine voice suddenly distracts Observer Alpha and she turns around.
"It's not entertaining, Purifier. It's fascinating... Very fascinating, I'd say." She answers with a cordial and composed smile.
"Sitting on your ass all day while watching a bunch of girls as they go to war with each other and end every single battle without the slightest bit of bloodshed? Sounds sooooo much fun." Says Purifier sarcastically, "Why don't you actually let me fight against those suckers instead of watching those poor quality battles? I could give you a much more entertaining show if you just let me kick some ass!" She continues, raising the tone of her voice.
"Do not be hasty, Purifier. Wait patiently for the right time. Eventually, it will come." Observer said as calmly as usual.
"Ugh, I'm getting really bored, y'know?? I want at least a quick warmup! I'm not asking that much, just a little bit of action!" Purifier insists, almost in an imploringly manner.
"Don't fret, we will soon be descending upon glacial waters and playing with an old friend once again..." Observer reveals while smirking mischievously.
"Wait... Are we going back to Russia??" Purifier is suddenly excited as she impatiently waits for Observer's response.
"We are."
"Hurray!!" Purifier starts hopping in place, she is very hyped up to hear these news, "When are we going? When are we going??"
"As soon as the stage is set... We'll have to wait until all the actors are gathered up. It will be an exciting show, Purifier..." Says Observer as she stands up. She turns around and begins walking forward slowly.
"The only missing elements are the actors. We have an Observer and a Tester to oversee the play... a Purifier to correct any mistakes..." She speaks as slowly as she is walking, "... And a Narrator to tell the story..." She finishes as she looks at you.
I thought I was clear enough earlier.
"Sorry, I couldn't help it." She giggles before looking away from you (me) and continuing to walk until she stops in front of one of the screens.
"This is where our show will be held... I will go check the situation for a while." She says before passing right through the screen and vanishing.

Apparently, each screen also acted as a gateway to access the respective timeline: Observer entered the one which I've narrated so far, the one we all know. She reappeared outside of the Academy at night. Even though not a single soul was around, Observer could see that a few rooms still had their lights on thanks to the windows. But that didn't matter much to her. She walked past the Academy's gates by pushing them open effortlessly, even though they were sealed shut. As the gates creaked, she made her way towards the entrance of the building.

The hallways were dark and quiet; but the dim moonlight entering from the windows created a somewhat surreal ambience, providing just enough light to see. Observer was not unsettled by this atmosphere, ominous and soothing at the same time, while she walked through the halls, knowing exactly where to go. She advanced at a slow pace, with no haste or apprehension, as though she was walking in her own home. She knew the building wasn't empty, but had no fear of being caught. Slowly and confidently she went, until eventually she stopped before a specific door.