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HQ was eerily quiet for a Friday night.
Usually, Killjoy could hear Jett’s sneakers squeaking down the hall or Phoenix blasting music through the mess hall speakers. But now only the low hum of fluorescent lights filled the corridors—everyone else was deployed.
Everyone except her... and Viper.
Killjoy leaned back in her chair, spinning lazily in the empty lab. “Guess it’s just us, huh? The dream team of science and sarcasm,” she muttered to herself.
Her wristwatch buzzed. Urgent briefing. Hangar 03. 1900 hours.
She groaned, though a smirk tugged at her lips. “There goes my Halloween movie marathon.”
Down the corridor, she spotted Viper—dark coat flowing, mask clipped to her belt, expression as sharp as ever.
“Oh. You’re my partner?” Killjoy asked, trying (and failing) not to sound too excited.
Viper raised a brow. “Don’t sound so surprised. Everyone else was already deployed when the request came through.”
With a grin, Killjoy quipped “So you’re saying fate paired us together? Scandalous.”
“I’m saying Breach was supposed to go with me, but he’s still in Morocco,” Viper sighed.
Killjoy’s face fell. “You’re saying I’m Breach’s replacement?” she exclaimed, offended by the mockery.
“Correction.” Viper fastened her gloves. “You’re better than Breach. He’d blow our cover in five minutes.”
That made Killjoy’s heart do an unprofessional little somersault.
Inside the hangar, a holo-table projected maps and dossiers. Brimstone’s voice crackled through comms:
“Mission codename: Phantom Harvest. Location: Moscow. Infiltrate a biotech front linked to Kingdom’s covert R&D division. High risk, but short-term.”
“Understood,” Viper said as she internalized the mission details.
Killjoy flicked through the digital files. “Ooooh, fake identities! What’s my alias?”
“Dr. Johanna Weiss,” Brimstone said. “Neurotech consultant from Berlin. You’ll pose as the fiancée of Dr. Alexandra Cross—”
Killjoy nearly choked. “Wait. Fiancée?”
Viper shot Brimstone’s hologram a deadpan look. “That detail is unnecessary.”
“You’ll draw less suspicion that way,” Brimstone explained. “Two scientists relocating to Moscow for research. Play it cool. It’s Halloween weekend, so the city’s full of cover—masquerades, parties, tourists. Use that.”
Killjoy couldn’t resist. “Guess we’ll fit right in, huh, A-lex-an-dra?” she teased, rolling the name like candy on her tongue.
Viper didn’t respond, but her jaw tensed ever so slightly.
The VTOL sliced through clouds over the Atlantic. Viper sat by the window, reviewing data. Killjoy sat across from her, pretending very hard not to stare.
“So…” Killjoy said, fiddling with her smartwatch. “Dr. Alexandra Cross. Sounds romantic.”
Viper didn’t look up. “It’s a cover. Don’t read into it.”
Killjoy pouted. “Right. Of course. Just a cover. Like how your background says you’re a molecular biochemist who— wait—ran a successful skincare line?”
“It’s called blending in.”
“You? In skincare?” Killjoy grinned. “Imagine the ads: ‘Tired of toxic exes? Try Viper Serum. It burns beautifully.’” She couldn’t help but chuckle.
Viper shot her a withering glance, but a hint of amusement colored her voice. “You’re insufferable.”
“Thank you,” Killjoy said brightly. “It’s part of my charm.”
After a moment, silence settled between them—the kind that buzzed with unspoken things.
Killjoy looked out the window at the endless dark. “Do you ever think about... what your life would’ve been like if Brimstone hadn’t found you?”
“Every day,” Viper admitted softly. “He recruited me when I was already halfway down a path I couldn’t turn back from.”
Killjoy smiled gently. “So he saved you?”
“No. He gave me a purpose.” Viper paused. “There’s a difference.”
With a nod, Killjoy watched her mentor-turned-crush in quiet awe. “Guess I was lucky, then. The Protocol was the first place that didn’t call me a prodigy freak.”
Viper finally looked at her—really looked. “Anyone who called you that was a fool.”
For the first time, Killjoy had no quick retort.
“Viper, I’m speechless—and I always have something to say” is all that Killjoy could think of in her moment of kilig.
x - - - - - - - - - - - - - - - x
Moscow’s chill bit through their coats as they stepped into narrow alleys, fresh stamps on their fake passports.
Their “leased apartment” turned out to be an old Soviet-era flat—creaky floorboards, a single bed, and a heater that buzzed ominously.
Killjoy dropped her duffel bag. “Oh look, one bed. How very convenient,” she said with a sly grin.
Viper shot her a glare. “We’ll take shifts.”
But that night, when Killjoy “accidentally” fell asleep debugging a surveillance drone, she woke up under a blanket—one she definitely hadn’t grabbed herself.
Smiling, she whispered, “You’re not as cold-blooded as you look, Alexandra.”
From across the room, Viper—pretending to read—murmured, “Go back to sleep, Johanna.”
—Moscow Apartment, Day 1—
The apartment was small, but it was warm.
A low hum of the radiator filled the quiet as Killjoy crouched by the door, fiddling with the lock and making sure her newest “upgrade” wouldn’t jam again.
Viper set her duffel bag down by the window, surveying the street below. Snow powdered the sidewalks outside, thin and silvery beneath the lamplight.
x - - - - - - - - - - - - - - - x
“Do you ever not modify the furniture?” Viper asked, arms crossed.
Killjoy looked up, a screwdriver between her teeth. “If I can make it work better, why wouldn’t I? Call it… German engineering, but make it cozy.”
“Cozy,” Viper echoed, her tone flat, but her lips betrayed the smallest upward twitch.
Killjoy grinned, blissfully unaware of it.
“Fine,” Viper said. “But if you blow the hinges off, you’re replacing them.”
—Moscow Apartment, Day 3—
The third morning came quietly. Killjoy was already up, goggles on, disassembling her drone in the kitchen—which had become half workshop, half breakfast counter.
Viper walked in wearing a dark robe over her turtleneck, a steaming mug in hand. “I assume that’s coffee I smell, not battery acid?”
Killjoy froze, halfway through screwing something in. “Uhh… both?”
Viper sighed and took a slow sip. “Lovely.”
Killjoy laughed, flustered and returned to her work. The silence that followed wasn’t uncomfortable—just delicate. She kept stealing glances at the older woman leaning against the counter, reading a dossier with sharp eyes and sharper posture.
Killjoy wanted to say something clever, but all she could think about was how effortlessly composed Sabine was—even here, even now.
“Hey, uh…” Killjoy cleared her throat. “If this mission wasn’t happening, what do you think you’d be doing?”
Viper didn’t look up. “I’m not one for hypotheticals.”
“C’mon,” Killjoy pressed. “You never thought about it?”
A pause. Then, softer:
“...Research,” Viper admitted. “Probably alone. Still in the lab. Some habits don’t die.”
Killjoy tilted her head. “That doesn’t sound so bad. I could visit. Bring snacks.”
That earned her a faint, genuine laugh—one that made the morning air feel less cold.
—Moscow Apartment, Night 5—
It was movie night, though neither of them officially called it that.
Their cover story required them to “blend in,” and according to the dossier, couples who stayed in often were less suspicious. So here they were: Killjoy on one end of the couch, Viper on the other, a single blanket shared between them.
Killjoy was doing her absolute best not to combust.
On-screen, a Russian black-and-white film murmured softly. Off-screen, Sabine’s presence was a gravitational pull—subtle, constant, impossible to ignore.
“Why are you fidgeting?” Viper asked.
“Me? Fidgeting? No way,” Killjoy’s hand jerked, scattering popcorn across her lap. “See? Totally chill.”
Viper raised a brow. “You’re about as chill as a thermal detonator.”
“...It’s a tense scene,” Killjoy insisted, voice a little too high. “Very engaging cinematography.”
“Just relax, maus” Viper said, turning back to the movie. “Before you go critical.”
The flickering light washed over their faces—and when Killjoy leaned forward to adjust the volume, their hands brushed.
Killjoy flinched to pull away, but Viper’s cool fingers closed around hers.
“Helps with the fidgeting,” Viper murmured.
Neither spoke again. The movie played on, but the scene on the screen faded into irrelevance, their touch lingering long after the final credits rolled.
—Moscow Apartment, Day 10—
Routine had settled around them: mornings for coffee, afternoons for data and calibration, evenings for dry banter that had grown easy, comfortable.
Too comfortable, Viper thought.
She’d caught herself noticing things—the particular frequency of Killjoy’s hums when she worked, the way her laughter filled every corner of the apartment. It was… unsettling.
When Viper found the engineer asleep at her desk, cheek smudging the ink on blueprints and a half-assembled turret by her arm, the professional thing to do was to wake her. Instead, she draped her jacket over Killjoy’s shoulders and left her there.
Killjoy stirred at sunset, blinking clearly “Oh. How long was I out?”
“Long enough to drool on the schematics.”
“Scheiße.” Killjoy groaned, mortified. Her fingers found the sleeve of the coat. “...Thanks for this,” she murmured, tugging it tighter.
“It was cold,” Viper said flatly. “Your teeth were clattering noisily.”
Killjoy tilted her head, sleepy grin spreading.. “You’re a sweet liar, Sabine.”
Viper paused, shifting her attention back to the datapad. “Your definitions are flawed.”
“I’m an engineer,” Killjoy said, smirking. “Redefining things is what I do.”
—Moscow Apartment, Day 14—
They had to play their parts that day: “Dr. Johanna Weiss” and “Dr. Alexandra Cross,” the married European researchers they were pretending to be.
Viper hated the wig. Killjoy adored hers.
Walking arm-in-arm through the busy streets, Killjoy’s grin was uncontainable. “You know, we look good together. I mean, professionally. For the mission.”
Viper didn’t respond immediately, eyes scanning the crowd. “You sound like you’re enjoying this too much.”
“Maybe a little,” Killjoy admitted, giving her arm a playful squeeze. “Can you blame me? You make espionage look like an art.”
Viper shot her a sidelong look. “And you make chaos look like a hobby.”
“Aww, thanks!”
“Not a compliment.”
But the corners of Viper’s mouth softened, and Killjoy caught it—the faintest smile that meant everything.
Later, at a small café to keep up appearances, Killjoy attempted to teach Viper how to eat pirozhki without looking like she was ready to draw a weapon. It wasn’t going well.
“Dr. Alexandra,” Killjoy teased, chin resting on her hand, “It’s food, not evidence.”
“I’m analyzing the filling.” .
“For poison?”
“For structure.”
Killjoy laughed. “Okay, wifey.”
Viper set the pastry down, studying her instead. “Dr. Johanna, is this… outing part of your experiment?”
Killjoy blinked, thrown off guard. “I mean, sure. Let’s call it that.”
—Moscow Apartment, Night 17—
A blizzard raged outside.
Inside, warmth, and two women working in comfortable silence. Viper pored over chemical readings; Killjoy debugged a sensor array.
Killjoy broke the silence first.
“Hey, why’d you join the Protocol anyways?”
Viper didn’t look up. “Because I was asked to. And because it was better than what came before.”
Killjoy’s hands slowed on the keyboard. “What came before?”
Viper paused, then set down her pen. “Things I’d rather not revisit.”
“Oh,” Killjoy said quietly. “Sorry.”
“Don’t be.”
They worked a bit longer before Killjoy spoke again, voice small, almost shy.
“You know, I used to watch your lectures before I joined VP.”
That made Viper glance up. “You did?”
“Yeah. You were kinda my hero.” Killjoy shrugged. “Still are, in a way.”
Viper’s expression softened, though she turned away before Killjoy could see it. “Heroes are overrated.”
“Maybe. But you’re still mine.”
They both returned their attention to their work. A moment later, Killjoy hissed and pulled her hand back as a soldering iron slipped.
Viper reached across the table quickly, taking the tool from her without a word.
“...Thanks,” Killjoy said.
Viper didn’t answer. She didn’t need to.
—Field Report Prep, Day 18—
The call came in. The mission was ready.
They had everything they needed—intel, location, cover.
Killjoy packed her gear slower than usual. “So… after this, things go back to normal, right?”
“Normal is relative,” Viper said while checking her pistol.
“Right. Relative.” Killjoy zipped up her case, hesitating. “I wouldn’t mind if our normal was still like this.”
That made Viper stop for half a second. “Jett was right. You talk a lot.”
“I talk more when I’m nervous.” Killjoy chuckled weakly.
“Why are you nervous?”
“Because… I don’t want this to be just a cover story.”
The silence that followed was heavier than the gear on the table.
Viper finally turned to her, face unreadable behind the mask she wore so well. “Let’s focus on the mission, Klara.”
“Right,” Killjoy nodded, forcing a smile. “Mission first. Got it.”
But her heart insisted otherwise.
—Moscow Apartment, Night 20—
It was the night before the mission, and Killjoy couldn’t sleep.
She stood by the window, looking out over the snow-dusted city, idly rolling a screwdriver she didn’t need.
Viper stepped in quietly, robe drawn around her. “You should rest.”
“Can’t. My brain isn’t shutting up.”
“You’re running simulations again.” Viper leaned beside her against the window frame beside her.
“Yeah, well, that’s my job description.”
“Of course.” A soft chuckle escaped Viper’s lips. The sound was rare, precious.
Killjoy let out a breath. “Do you ever get scared, Sabine?”
“Always,” Viper said. “That’s how you know you’re still alive.”
Killjoy looked at her—really looked—and something inside her chest ached.
“Then I guess I’m really, really alive right now.”
Viper met her gaze, eyes gentler than Killjoy had ever seen them. “Go to bed, Klara.”
Killjoy hesitated, but nodded and stepped away from the window.
She was almost out the door when Viper spoke again, quiet and careful:
“You’ve been working well. This month.”
Killjoy’s smile was small but satisfied. “Good night, Sabine.”
—Mission Night—
The masquerade blurred into chandeliers and perfume, gilded masks catching amber glow. The ballroom—an opulent relic of Tsarist Moscow—shimmered with the grandeur of old wealth. Marble columns rose like pillars of frost beneath vaulted ceilings painted with fading cherubs, while the chandeliers dripped with crystal tears that chimed faintly.
Outside, snow pressed against the windows, muffling the city. Inside, warmth and decadence hid tension under laughter and the mingling scents of champagne, cigar smoke, and violet perfume. Silk gowns brushed against military coats, and the orchestra’s low waltz echoed through the marble, drowning out the whisper of secrets traded behind masks.
At the top of the grand staircase, two newcomers paused—a striking couple draped in understated elegance.
Viper’s black lace mask concealed everything but the emerald glint of her eyes. Killjoy, adjusting her cufflinks, tried and failed to look like she wasn’t impressed by the ballroom beneath her gold-and-ivory mask.
“Play it cool,” Viper murmured. “You look like you’re here for a historical tour.”
“Can you blame me? I don’t usually get invited to supervillain fundraisers.” Killjoy tugged uncomfortably at the neckline of her emerald gown, clearly wishing for a drone controller instead of a champagne flute.
Viper allowed the faintest ghost of amusement tugging at her lips. “Just remember, we are the villains tonight.”
“I just—there are too many people,” Killjoy whispered. “Too many unknowns.”
“That’s why we’re here” Viper replied, her tone calm but watchful. “Focus, Johanna.”
Killjoy’s smile twitched. “You only call me that when you’re pretending not to worry.”
Before Viper could respond, the music glitched—just a blip but enough. Killjoy’s gaze snapped to the balcony. A man in a white mask had just signaled toward the back door.
“Signal confirmed,” Killjoy muttered, pressing the comm in her ear. “They’re on the move.”
“Split right.” Viper’s hand slipped into her clutch—her silenced pistol hidden under silk and gold.
Then chaos.
The first gunshot was almost blended with the orchestra’s crescendo. Glass shattered; guests screamed. Viper fired three precise shots, dropping one of the masked infiltrators before they could reach the stage.
Killjoy ducked behind a table, activating her wristband. A pulse of neon yellow rippled across the floor as a micro-drone swarm zipped out from under her gown—a literal buzz of death.
“Left flank clear!”
“Stay low,” Viper ordered, carving her way through. She was every inch the scientist turned soldier—movements sharp, deliberate, merciless.
But the enemy was fast. An armor-piercing round ricocheted off a pillar, splintering marble into Viper’s arm. She staggered, her mask half-broken, venom canisters hissing at her side.
“Sabine!” Killjoy yelled.
“Stay down!” Viper barked, firing again.
But Killjoy had already moved.
She saw the muzzle flash before anyone else—saw where the bullet was headed—and threw herself between Viper and the shooter.
The shot tore into her shoulder with a crack of bone and searing pain. She hit the ground, vision blurring.
Viper screamed—nothing like the composed scientist, the cold agent. Just Sabine.
She dropped beside Killjoy, firing blindly at anything that moved. Blood slickened her glove as she pressed against the wound.
“Klara, look at me. Don’t you dare pass out!”
Killjoy tried to laugh, but it came out broken. “You… actually sound worried. Never thought I’d see that day.”
“Shut up,” Viper hissed, voice trembling. “You should’ve stayed behind cover.”
“If I did,” Killjoy rasped, “you’d be dead.”
“I told you—”
“And I ignored you,” Killjoy interrupted weakly. “You’re worth it.”
Viper’s jaw clenched. The room was chaos—sirens, smoke, broken glass—but it all dissolved into Killjoy’s hand gripping her sleeve, eyes fading between pain and adrenaline.
“You know, Sabine… we played a couple this past month but… I wasn’t pretending.”
Viper froze, staring at her. “Don’t—just don’t say that now.”
“We’ll talk later,” Killjoy breathed, “in your lab?”
“Later,” Viper agreed, her voice breaking. “But only if you stay awake.”
The evac team burst in with a storm of light and rotor blades.
Viper’s hands never left Killjoy’s wound, even as the medics tried to pull her back. “She’s going into shock—stabilize her now!”
They loaded Killjoy into the transport. Viper climbed in after her, ignoring the protests. Her mask was gone, her face pale and streaked with soot. She looked nothing like the composed scientist everyone feared.
Killjoy’s eyelids fluttered. “You… didn’t have to come in with me.”
“Of course I did,” Viper said with a voice so hoarse. “You think I’m leaving you after that stunt?”
Killjoy managed a faint, smug grin. “Knew you cared.”
“Be quiet,” Viper muttered, clutching her hand as the engines roared. “Save the energy. We’re not done yet.”
Killjoy slipped under before she could answer.
x - - - - - - - - - - - - - - - x
Back at HQ, the med ward glowed cold and sterile white. Killjoy slept for days, her shoulder swathed in healing nanoweave. Sage and Reyna alternated shifts, whispering about how terrifying Viper had been during the extraction.
When Killjoy finally woke, her vision cleared around familiar green—Viper, slumped beside her bed, eyes rimmed with exhaustion.
“You look awful,” Killjoy croaked.
Viper didn’t smile. “You almost died.”
“Would’ve made a cool Halloween costume.” Killjoy tried to sit up. “Zombie girlfriend.”
Viper exhaled—half sigh, half laugh. “You’re insufferable.”
“And you stayed.”
“I said we’d talk when you were healed.”
Killjoy winced as she shifted. “Guess I shouldn’t die yet.”
“Correct.” Viper’s voice was soft, and for once, unguarded. “Rest, Johanna. We’ll finish the conversation in my lab.”
“You promise?”
Viper paused at the door. “I don’t make promises I don’t intend to keep.”
x - - - - - - - - - - - - - - - x
Later, in the dim glow of Viper’s lab, Killjoy sat cross-legged on the counter, tinkering with a battered drone.
Viper adjusted a centrifuge across from her.
“You sure we’re okay skipping the debrief?” Killjoy asked, watching the green lights blink on Viper’s workstation.
Viper’s shoulders lifted in a calm shrug. “Let Brimstone wait. He owes me after you took that bullet.”
Killjoy smirked. “Technically, protecting you is part of my job. You’re welcome.”
Viper shot her a tired look. “Don’t do it again.”
“Oh? Would you miss me?”
“That’s not what I said.”
Killjoy hopped off the counter, stepping closer. “Then what are you saying, Sabine?”
Silence hummed between them.
Viper turned, placing a gloved hand gently on Killjoy’s uninjured shoulder. “I’m saying you terrify me sometimes,” she said quietly. “Because you make me care.”
Killjoy’s breath caught—words failing her for once.
Then, in a rare breach of her own protocol, Viper leaned in and brushed a quick kiss against Killjoy’s cheek.
It was a brief touch—barely there, but enough to send heat rushing up Killjoy’s face.
“That stays between us,” Viper murmured.
Killjoy grinned through her blush. “Secret’s safe, Dr. Cross.”
Viper’s lips turned into the rarest smile. “Good. Now help me recalibrate this mixer.”
“Right away, partner,” Killjoy beamed, still grinning.
EPILOGUE: After the Masks
Two nights later, the HQ was alive again with music and activity—someone had decided that even if half the agents missed Halloween, they’d celebrate anyway.
Killjoy, arm still in a sling, was halfway through wiring a pumpkin-shaped drone when Yoru plopped onto the couch beside her.
“So,” he drawled, “heard you and Viper played house in Moscow.”
Killjoy blinked. “What—who told you that?”
Yoru tossed her a data chip. “Brimstone’s mission report. ‘Classified’ my ass. Whole Protocol knows you two went undercover as an engaged couple.”
Across the room, Jett burst into laughter. “Wait—engaged? With rings and everything?”
Killjoy groaned, hiding her face behind the drone. “There was no ring! It was part of the cover story, okay? Totally professional.”
“Sure,” Phoenix said, sipping a cup of cider. “Very professional. Especially the photos Sage found in the field feed.”
“What photos??”
On cue, Sage’s holo-display flickered to life: a still frame of Killjoy and Viper at the gala, their hands brushing in a moment that, annoyingly, looked intimate.
The entire room erupted in oohs and aahs.
Even Raze whistled. “Ay, vocês tão fofas demais! You look like you were about to kiss!”
Killjoy’s face turned defcon red. “We were literally surrounded by armed targets! Can you all not—”
The door slid open.
Viper entered. Silence fell instantly.
Everyone scattered to find something to do—checking gadgets, adjusting armor, or very conspicuously walking out.
Killjoy muttered, “Cowards.”
Viper raised an eyebrow. “Am I interrupting something?”
“Just my public humiliation,” Killjoy said sheepishly. “Apparently, our engagement leaked.”
Viper sighed. “Of course it did.”
She reached into her coat pocket and, to Killjoy’s surprise, held out a small box. Inside sat a sleek circuit ring, glowing faintly with yellow light.
Killjoy blinked. “Sabine…?”
“It’s a signal jammer disguised as jewelry. Thought it you could use it since everyone assumes we’re a couple now.”
Viper slid it onto Killjoy’s ring finger.
“So,” Killjoy said slowly, “you made me a jammer shaped like a ring. Very practical and convenient, given the rumors.”
“Exactly.”
“And not because you actually—”
Viper shot her a look that said don’t push it. But the corner of her mouth lifted—the one Killjoy now knew meant maybe.
“Happy belated Halloween,” Viper said, turning to leave.
Killjoy couldn’t help it; she called after her, “You know, Sabine, now the rumors are gonna get worse! Everyone’s going to think you’re courting me!”
Viper lifted a hand in mock salute. “Don’t flatter yourself.”
“Too late.” Killjoy twirled the glowing ring, cheeks warm..
From the hall, Phoenix shouted: “DID SHE JUST PROPOSE?!”
Killjoy was fast, slipping on her goggles. “It’s classified.”