A/N: Welcome back~

Time for a little more calm before the storm... and some insight into Alterprise herself~

Enjoy~


Stardust

Chapter 25: Imposter

The testing ground within Base Upsilon was a strange place.

At first glance it was a metal room, no bigger than many tennis courts. Then, with a simple manipulation of the technology behind it, and it could become more expansive than the Pacific Ocean and with a geography simply impossible in reality. Winds could change direction at a whim, entire ocean currents could reverse, and even entire landmasses could be reshaped within seconds to form the desire battlefield.

Which made it an ideal place for the Sirens themselves, especially the non-combat models, to hone their skills. Though they were machines they still required such a testing ground, mostly for experimenting with new weaponry in a practical environment or for honing their reflexes – 'keeping in shape', as it were. Purifier was especially fond of it, being a combat model herself and inbuilt with a lust for battle she not only honed her combat effectiveness against the test dummies thrown at her, but also for the sheer fun of it – a fun that the likes of Observer Alpha and Tester Beta clicked their tongues in distaste at, but one that neither bothered to correct.

However, whilst Alpha and Beta took no outright pleasure in combat, both were far from disdainful of it.

Something Alterprise herself found out once again.

Skree~!

''Mn-!'' Alterprise winced as a golden laser passed over her shoulder, scorching away the cloth there and singing her skin.

Reacting swiftly the carrier leapt backwards, feet skipping over the calm ocean's surface – only to have to leap again as another of Alpha's laser cannons fired, sending a shrieking beam of light tearing through the water and superheating it into steam. Alterprise merely got out of the steam's path, mentally directing her dive bombers down and making them twist and turn as they dived, dodging the shorter but far more numerous lasers that shrieked up into the air like a barrage of anti-air bursts.

However no matter how hard she tried Alpha's accuracy was too good, and soon all three of her dive bombers were blown to smithereens. Only one got their bomb off, sending it whining down – before it splashed harmlessly into the ocean, a small column of water the only sign of its impact as it detonated beneath the waves. Undeterred Alterprise followed up on her failed attack; two golden arrows manifesting over both of her shoulders and firing with naught but a mental command, closing the distance within a second.

''Hmph.'' Alpha raised a tentacle, letting the arrows impact it and get embedded; allowing the Siren to smash the arrows in two with a second tentacle. ''Faster.''

Alterprise grimaced and obliged, pushing herself to her limit as she dodged another incoming laser. This time Alpha closed in for melee, the diminutive Siren lethally fast as she closed in on her – and with a vigour one wouldn't expect from the short Siren she attacked, a fist thrown with machine-guided accuracy. Alterprise was forced to block with her arm, wincing from the bruise-inducing force that struck her guarding arm, only to gasp as a second arm darted past her guard like a viper, striking her in the kidney with a palm strike.

However while Alpha had deceptively good melee skills, she also still lacked reached – something Alterprise exploited, swiping a back-hand out and forcing Alpha back. When the Siren attempted to close the distance Alterprise kept her back with precise jabs of her bow, the sharpened end narrowly missing the Siren but still succeeding in driving her back lest she get clipped in the process of attacking; the thought of being injured from simple arrogance quelling Alpha's veiled ferocity.

At the same time Alterprise directed some of her torpedo bombers to come in, syncing the attack with the dive bombers still circling high above on standby. As one the two air groups converged, one diving from above and the other coming in low from the right. Alpha merely glanced at both, the gears in her mind almost visible as they turned, working out the most effective counter to both attacks. Alterprise used that momentary delay to raise her bow, and fired her nocked arrow without delay.

Only to purse her lips as Alpha whacked the arrow aside with a lightning-quick tentacle, sending the arrow flying past her cheek and into the ocean behind her.

Then without hesitation Alpha's absurd number of laser cannons tilted, glowed – and with a chorus of shrieks they fired. Lasers of all kinds of width and length shrieked skywards, flying past her swerving dive-bombers or past her incoming torpedo bombers, the Devastators tilting slightly to avoid them. However they didn't have the same manoeuvrability as her dive bombers did, causing several to be hit directly and plunge into the ocean, some not even aflame – their entire airframe simply gone beyond the wings, leaving said wings to corkscrew through the air and skip across the ocean's surface.

However several reached their stationary target and dropped their torpedoes. Their wakes could be seen on the water's surface, prompting Alterprise to attack with several hastily-summoned arrows, distracting Alpha somewhat. The Siren however multi-tasked with ease, unleashing several golden lasers at her to keep her busy whilst still peppering the sky above her head with laser fire; her inbuilt sonar system allowing her to keep track of the incoming torpedoes, and then casually step out of their path. However the mere fact she had to move deprived her cannons of some accuracy, allowing a narrow few dive bombers to drop down close enough to drop their thousand-pound bombs...

...all of which missed, splashing around Alpha's motionless frame.

''Hmph.'' Alpha merely hummed as the planes flew over her head. ''Your precision needs improving.''

''You're a hard target.'' Alterprise countered stoically.

Alpha hummed but didn't attempt to counter that, raising her hand. ''Test Setting Zero.''

Around them the world seemed to flicker; the ocean growing dimmer then brighter, the sky wobbling, the distant islands fading – before with a low, mechanical whine the entire ocean disappeared, and the room transformed back into a far smaller metal room. On reflex Alterprise de-summoned her planes before they could crash into the metal walls of the testing ground, their roaring engines dissipating into nothingness, leaving just the brief echo of their tenor before they disappeared.

''That's enough for now. I'll have you aid me later once I've adjusted by eyesight for anti-air applicability.'' Observer Alpha remarked languidly, turning away to leave.

Alterprise pursed her lips, and decided to stop her. ''Alpha.''

''Hm?'' The Siren paused, glancing back at her. ''What is it?''

''...I want to go to the base.''

Even though she didn't specify what base, Observer Alpha was all too aware of what she meant – something that brought a smirk to the Siren's pale lips. ''Hmhm, you may. Provided that you do not engage in combat, nor reveal the extent of our infiltration abilities.''

''I won't.'' Alterprise nodded.

''Then be off with you.'' Alpha regally waved her off, not even bothering to walk out of the room – having her tentacles simply function as legs and carry her out. ''Do not waste time.''

At that Alterprise merely dipped her head in a nod, departing the room with equal swiftness.

X-x-X

Exiting out of a portal a fair distance away from the base, Alterprise gradually made her way towards it under the cover of night.

Even with the black sky on her side however it was no simple task. Aircraft flew patrols over the land and seas with bothersome regularity, forcing her to frequently duck into cover behind old buildings or beneath fallen trees. Her black coat came in handy to blend her in, allowing her to gradually make her way past the rings of defences that now surrounded the base, entering it through the forest that reached the side of the base and making her way through it.

Alterprise carefully shifted through the bushes, only the slightest of rustling made as she walked – mindful to look as casual and deep-in-thought as possible to not arouse suspicion. She succeeded; walking out of the sparse forest from the dirt path within and passing a group of soldiers who paid her no more than a surprised glance, perhaps wondering why 'Enterprise' would be taking a walk so late in the night, but none moved to stop her.

Sweeping her eyes around Alterprise noted all the locations, all the persons about despite the late hour. So many targets, so many openings.

But no, she knew what she came here for.

Yorktown.

Alterprise carefully kept any emotion from showing on her face, walking down the cobblestone path that was still being repaired in places. Despite the late hour many people were still up and about; spotlights constantly swaying and scanning the skies for any Siren bombers that might try and catch the fleet unawares. Anti-air emplacements were manned both at the shoreline and throughout the base as well, whilst shore batteries were either constructed or undergoing said construction, guns of varying but noteworthy sizes aimed towards the quiet ocean.

She had to admit, even to herself, that the defences were quite impressive. She doubted anything short of the more powerful Sirens like Alpha and Purifier could shrug them off, and even then not in a battle of attrition. She knew for certain she wouldn't be able to survive under such an onslaught. Chasing that thought from her mind Alterprise stepped off the path, crossing over a patch of uneven dirt towards the field hospital set up near the Ironblood dorms, quiet as a ghost as she passed by some more soldiers who were following a cruiser – Admiral Graf Spee? – but none paid her any mind.

And soon she passed by one of the soldiers guarding the tent itself, giving him a brief nod before prying open the stiff curtain, stepping inside. Twin rows of beds greeted her, many of them empty, and perhaps recently so – but many others were still occupied by sleeping Ship-Girls. Thus Alterprise kept her footstep silent, each step purposeful and carefully done as to not disturb the flooring underneath, a skill she gained from her other half's years of trials and tribulations.

Alterprise purged that thought from her head as she laid eyes on what she came for.

'Yorktown...' Alterprise's golden eyes locked onto the carrier.

The aforementioned carrier laid fast asleep beneath her quilt, snoozing softly and unaware. Seeing that Alterprise moved closer up to her bedside, raised her hand-

-and then laid it on Yorktown's cheek.

''...hah...'' Alterprise let a soft breath pass her parted lips.

It was foolish. Silly, even, for her to come all the way out here, to literally walk into the base of her enemies just to look at Yorktown... but, she still did it. Some unknown, strange force that made her, no, compelled her to do it. A gnawing in her chest that begged just to lay eyes on the carrier who couldn't truly be called a sister, but something of a half-sister, given her sirenic origins. It was unfathomable to her, this attraction, this... desire for her. A longing, almost.

Alterprise's brow furrowed somewhat. Did her other half also feel this way, or was this something unique to her? Was it because the Sirens made her, or was it because she was different in some way? As far as she knew she had the same mind as her other half; surely, then anything she didn't understand, neither would her other half? Or was she warped in some way by the Siren's machinations, her mind unable to comprehend what her other half could, in the same way the Sirens couldn't truly fathom some aspects of mankind and its guardians?

She didn't know. And it frustrated her.

''Mn...'' Movement made Alterprise stiffen, watching as Yorktown scrunched her brows up and shifted.

Not wanting to be caught Alterprise removed her hand with haste, and without a word turned and left – unaware of the pair of eyes peering at her from the bed next to Yorktown's own.

Stepping outside Alterprise exhaled a heavy breath, frustration still lingering in her soul. Part of her regretted coming here in the first place now, but another part of her almost wanted to stay, to work through the uncertain feelings in her heart. It was perhaps because of those conflicted feelings that Alterprise found herself aimlessly walking towards the sea, heading for the seawall as if the slow-churning tides would give her an answer.

They didn't. Stood by the edge she could feel the cold night wind blow into her face, accentuated by the frigid seawater the further cooled the air, but no answers came to Alterprise – the only comfort she got being the pleasant sight of the sea, so much calmer than the one at Base Upsilon. It felt much more natural than the chaotic tides the Sirens had for whatever reason; they certainly didn't have it for aesthetics, that's for sure.

There was a reason the Sirens all wore similar styles of dress, and it wasn't because of fashion.

''Hm?'' A semi-familiar voice startled Alterprise out of her thoughts. ''Enterprise? What are you doing up so late?''

Essex.

''I...'' Alterprise paused for a second to think. ''Thinking?''

''...at this time of night?'' Essex sounded dubious about that, but not inherently suspicious.

Alterprise opted to change the topic. ''What are you doing up so late?''

''Preparing to sortie in a couple hours before daybreak.'' The blue-haired woman answered lightly, jerking a thumb over at her waiting hull. ''Loading up ammunition, fuel, the like. Gonna whisk Zuikaku and Shoukaku with me alongside some escort and a couple heavier ships to hold down the fort until the rest of the fleet is ready.''

''I see.'' Alterprise dipped her head in a slight nod. ''Erm... stay safe.''

''Heh, course I will.'' Essex didn't pay her awkwardness much mind. ''Any orders from Henderson about it?''

Alterprise paused to think, gauging whether such a thing would've been likely to occur and the risk of saying something incorrect – before she went with something more neutral. ''A couple. Mostly just being prepared for anything.''

''Guess you're being held back as part of the main strike force, then.'' Essex bought it. ''Look out for the others while I'm gone, 'kay? N-Not that I doubt you or anything, just... y'know. Keep everyone safe.''

Alterprise shifted, looking away. ''Right. I'll do that.''

She couldn't bring herself to meet Essex's eyes.

Not with the knowledge that it was her bombs that had dealt so much damage to the base itself. While she didn't directly take the lives of any Ship-Girls, she aided in it by disorienting and wounding them, leaving them easier prey to the Siren aircraft that followed her Dauntless dive bombers or the warships that shelled the base after her planes were shot down.

A hand landed on her shoulder, squeezing. ''I know you will. You always do your best, senpai.''

Alterprise tilted her head, glancing back at Essex – finding the carrier smiling with eyes shut, unintentionally missing the fact that Alterprise's own eyes were far from the familiar lavender Essex would expect.

Yet despite the words not being directed at her, but rather at the Enterprise Essex thought she was speaking to...

...they still brought her a strange comfort.

''...Mm.'' Alterprise petted Essex's hand. ''See you at New York.''

''Heh, getting ahead of yourself?'' Essex jokingly said, misinterpreting. ''We still don't know for certain if they'll attack there.''

Alterprise smiled faintly, turning away. ''No, they will. Also...''

''Hm?''

''...before you leave, pass a message onto Belfast for me.'' Alterprise decided to take a gamble. ''Tell her, verbatim... Upsilon, seventh year. She'll know what it means.''

Essex blinked, bewildered by the nonsensical information. ''Um... sure, senpai. See you.''

Alterprise dipped her head in a nod, bidding her 'comrade' goodbye and walking away from the seawall – taking the long way around the base to make sure she was out of sight.

Only then, with few eyes on her did Alterprise wander back into the forest's dirt trek, forcing a deep-in-thought expression onto her face to mask her true intent, her brow furrowed emphatically. Soon she grew out of sight, the darkness masking her presence and allowing her to bolt into the woods itself – sneaking away into the shadows.

Though even as she made her way to the rendezvous point to return back to Base Upsilon, a thought still lingered in her burdened mind.

'I always do my best, huh...'

X-x-X

Enterprise woke up with an odd feeling, one that could neither be placed nor discerned.

Brushing it off as a waning wisp of a dream Enterprise shifted up on her elbows, puffing out a sigh. Once again she found herself within Belfast's bed, an idle glance over at the clock on the bedside table reading just past eight in the morning. It was a somewhat overcast day; the grey skies outside bringing a gloomy light into the regal bedroom. Enterprise took a moment to cast her gaze over it all, soaking it in as she shook off the lingering remnants of sleep.

Then with a quiet murmur Belfast soon shifted, the carrier's own movements helping the process along – until with a groan Belfast cracked her eyes open. For just a few seconds she stared, caught in a sort of daze, and eventually groaned it away and shifted onto her back, lolling her head slightly to the side and looking up at her. A smile then crossed Belfast's face, bringing one to Enterprise's own on reflex alone.

''Good morning.'' Belfast breathed.

''Morning.'' Enterprise responded in kind.

Belfast just smiled, and after sparing a glance at the clock patted the spot next to her. With a light grunt Enterprise let her elbows slip from under her, easing herself back down against the pillows next to Belfast – both just laying there for a minute. With how hectic their days had become post-attack, even a few minutes of quiet reprieve before the day's commencement was a welcome gift; a time to just relax in each other's presence. A thing that had both become increasingly common, and increasingly easy for Enterprise herself.

It was after several minutes of peaceful silence that Belfast shifted upright. Still smiling gently she gestured to the shower, silently asking if she wanted to go first, prompting Enterprise to decline with a shake of her head. Humming lightly Belfast slid out of their shared bed, her long nightgown fluttering behind her ankles as she meandered over to the adjoined door and disappeared behind it. Half a minute later the sharp hiss of a shower could be heard from behind the door.

''Mn...'' After a few minutes of listening to the pleasant soundtrack Enterprise sat up herself, tossing the covers off and making her way over to where Belfast had kindly left her uniform on the desk – not just laid there, but also ironed and smoothed neatly out.

Collecting them over her arm Enterprise didn't need to wait more than a minute, practically having memorised how long Belfast usually took – and true to her predictions the bathroom door clicked open after just a few more seconds, allowing Belfast to step out, naked aside from a fluffy cream towel wrapped around her from bust to knee and with a towel in her hair.

''You may go in now.'' Belfast said with a smile. ''Water's still warm.''

Bidding her a casual thanks Enterprise passed her, slipping inside the bathroom behind her. And as per every morning before she fell into a strange, almost pleasant routine, doing the usual necessities and slipping under the warm spray of the shower, washing away the sweat and grime and taking the time to enjoy the feel of the water running over her skin. Despite all that had happened, and all that would come so very soon... she felt peaceful. A feeling that, strangely enough, Belfast inspired.

Perhaps because of how the maid conducted herself. Belfast was gentle, obliging and willing to fold to make things easier for her – but she also stuck to a routine. Breakfast, lunch and dinner at set times, waking up and going to bed as roughly the same times, daily duties at set times; she had a structure to her that Enterprise had sorely been lacking since her capture at the hands of the Sirens. Adding her desperately-needed support during her brief imprisonment, and she had come to see Belfast as far more than just a comrade. She was a true friend; someone she considered on the same level as Essex and Washington.

'Hopefully nothing bad happens...' Enterprise mused quietly as she stepped out of the shower, drying off.

She knew if the attack really did happen, then she'd be tied up confronting Alterprise – of that, she was certain. She couldn't afford to look out for Belfast whilst also fighting her sirenic counterpart.

Thus, she'd just have to put her trust in Belfast's ability to survive such a fight, and wait for her to return to her.

Shaking off the thought Enterprise finished drying off; languidly putting her clothes on and brushing her teeth before the mirror, at last escaping the warm bathroom. An expulsion of steam followed in her wake, the bedroom cooler – aided in part by the open window. Belfast stood off to the side out of sight of the window, underwear on and in the process of putting her dress on; politely leaving her back to Enterprise herself.

''Thanks.'' Enterprise said out of a matter of habit, looking away from Belfast and approaching the bed instead; taking a moment to make it for her.

''It's quite alright.'' Belfast amicably said, glancing back at her. ''Though... if I may be bold and inquire about something, Enterprise?''

''Yes?''

''What was your time like with the Sirens? Truly?''

Enterprise paused only momentarily, but the lapse was enough to draw a softer gaze from Belfast herself. ''You don't have to speak of it if you don't wish to. I merely worry about what burdens your mind.''

A prolonged pause answered her, broken several moments later by Enterprise's slow, but firm voice.

''It was tough.'' It felt like a blatant understatement, but it summed up Enterprise's thoughts well. ''The Sirens don't trick you. They layer deception upon deception, tricking you into tricking yourself. They lie, they omit parts of the truth, and even when they tell the truth you're so hard-wired to not believe them that you end up lying to yourself without them needing to do anything.''

''I see...'' Belfast murmured, cloth fluttering as she pulled her dress over her head. ''And what about now? How are you feeling?''

''...I'm worried about Alterprise. What tricks she'll have, what new strategies she'll use...'' Enterprise honestly confessed, her hands slowing as she straightened out the bed cover. ''...it's frustrating, in a way. Trying to figure out a way to beat myself.''

''Surely though her weaknesses are your own?''

''That's the problem. I don't have any.'' Enterprise stated, before bashfully tacking on. ''Er... at least that I'm aware of. The Sirens kind of trained me to not have any if I could help it.''

Belfast let out a musing hum. ''Then what about overwhelming firepower? Surely your counterpart can't sustain a fight against most of our fleet carriers at once?''

''Maybe...'' Enterprise wasn't entirely sure.

At that Belfast smiled softly, her footsteps quiet as she walked over to her side and laid a hand on her shoulder. ''Consider it. Your time with the Sirens may have conditioned you to rely solely on yourself, but that was then, and this is now. Your sisters, Saratoga and Essex, Washington, Miss Shoukaku and Miss Zuikaku... even I, too. We all stand behind you.''

Belfast's eyes grew soft. ''You aren't alone anymore, Enterprise.''

Enterprise flushed, looking aside. ''I... thanks, Belfast.''

In response Belfast snaked an arm around her and pulled her into a light, but firm hug, petting her back soothingly. ''Anytime.''

They were interrupted by the sound of knocking at the front door, prompting the duo to break off the hug with pink cheeks. Flashing her a slight smile Belfast hurried over to the door, adjusting her dress as she walked and smoothing out the creases, her hair already brushed and only lacking her signature frilled headband. Hastily making herself look busy looking out the window Enterprise keenly listened as the door clicked open – and a startlingly familiar voice came from the hallway outside.

''Good morning, Belfast. Your sister Edinburgh stated that Enterprise was here, yes?'' Akagi's voice was smooth but without smugness; if anything an undertone of suspicion lingered on her tongue.

''Why yes, she is...? For what purpose do you need her?'' Belfast inquired politely.

''Merely to confirm a suspicion of mine.'' Akagi responded.

Enterprise moved away from the window and into line-of-sight of the doorway, instantly earning Akagi's attention. The fox-woman stood clad in her usual outfit, only a few bandages around her shoulder but otherwise back to full health. Belfast stood off to the side of the door but still near it if she needed to get in Akagi's path; a protectiveness that Enterprise privately found flattering.

''What is it?'' The silver-haired carrier asked, a light frown crossing her visage.

Akagi stared at her for a second, eyes examining her visage with unusual intensity. ''Do you have a habit of sleepwalking, Enterprise?''

''No?''

''And were you here all night?'' Akagi spared a glance at Belfast at that.

Enterprise ignored the embarrassing implication; an uneasy feeling building inside her. ''As far as I'm aware. Why? What brought this on?''

''You were in the field hospital last night.'' Akagi revealed with grim eyes. ''You went to Yorktown. Though all you did was stroke her cheek, your eyes... weren't yours. Cold, and gold.''

'Gold?' Enterprise's befuddlement lasted all of a single second – realisation hitting her like a freight train. ''Alterprise...''

Almost in-sync Belfast came to a similar conclusion, a perturbed expression crossing her face. ''That Siren... what would she gain though, from doing that...?''

Akagi looked between them and hummed. ''I'm not sure. Though, at least, we can rule that your apparent doppelgänger can disguise herself as you easily enough to walk right into the base. And presumably back out, given neither I nor Kaga have seen a look-a-like of you walking about. I've already contacted the Commander about it and he's taking measures to prevent this in future. I have not told Yorktown, as of yet.''

The carrier then shifted, pulling out an envelope from under her arm. ''Oh, also, this was outside your door, Belfast.''

Blinking slightly Belfast accepted the mail with a polite thanks, popping open the rather simple envelope – the words 'To Belfast' scribbled in pen across it. Rather than any formal letter or message however only a plain piece of paper laid within, one torn slightly at the corners from how hurriedly it'd been shoved into the envelope, with the writing done in messy pain clearly done by someone in a rush.

Akagi moved to leave then, giving a polite nod to Enterprise and Belfast – only to be stopped by Belfast's own mutterings.

''What...? This doesn't...'' The maid frowned severely at the letter, then glanced over at Enterprise. ''Forgive me, Miss Essex isn't very clear here. Perhaps she intended this for you, Enterprise?''

Enterprise blinked, accepting the letter. ''I don't remember telling her I was staying with you, though...''

Her words trailed off as she laid eyes on the contents of the letter, however.

[Hey Belfast, Enterprise told me to tell you, quote, 'Base Upsilon, seventh year'. No idea what it means, but I guess it's code for something? Either way, sorry for bothering you! -Essex]

''What?'' Enterprise frowned deeply. ''I never told her-''

It was then, almost like triggering an old memory, the meaning came to her. Of a name she'd only ever heard spoken by Observer Alpha and Tester Beta, murmured usually when she was presumed unconscious or unable to hear – information deliberately kept secret from her. Base Upsilon. And on her seventh year in Siren captivity, she escaped from something akin to a base.

''Upsilon...'' Enterprise breathed. ''That's where... I escaped from...''

No further conversation could be had, however, as the shrill ring of an alarm rung over the whole base – alongside the resounding voice of the Commander echoing over the PA system.

''Siren forces have launched an attack on New York! All fleet members muster to their assigned rally points!'

The attack had begun.

[END]


A/N: The amount of people who expected Alterprise would try and assassinate Yorktown was surprising~ She's an unpredictable one, though~

See you all next time in Chapter 26: Reflections

No sneak peek this time, heheh~