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For Science!

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There’s something about Kara recently. 

They sat next to each other on the usual couch for the usual bestie lunch date, cheerfully carrying on conversations about how their day was going. Though within the back of her mind, Lena couldn’t help but notice some changes about her blond-haired,  blue-eyed companion. 

Lena knew that Kara was the red-caped hero of National City. A pair of glasses and a ponytail was hardly a cover against the Luthor woman’s intellect. After a few months of emotional tryst and heated arguments about trust, they were now closer than ever before. So with Kara’s secret out in the open, Lena couldn’t help but notice that a few changes started to occur in the past week.

Kara’s honey-dipped skin was glowing with perspiration, for one. Kryptonians don’t sweat easily, not in mid-summer on the hottest day in metropolis concrete jungle during normal activities. The next thing that got Lena’s attention was the smell. Not unpleasant though, she had always found Kara’s natural scent rather nice, but in the past few days… she had swooned one or two times to the increasing pungency of crushed pineapple and spiced fruits. She could barely eat with the scent overwhelming all her senses. It was rather distracting to say the least.

“Did you change perfumes recently?” Lena asked politely whilst poking at the salad Kara brought her.

It was just like Kara to get self-conscious at the question, twisting her fingers like she does when  nervous. Lena loved it when she did that. As if she, Lena Luthor, can make an invincible omnipotent being squirm in her place.

“Uhh, nope.” Kara chuckled lamely, pushing her glasses back, seemingly to shift her blue gaze over Lena’s neck and down to the open expanse of her cream-colored blouse. At first, Lena thought she had spilled something and stained the fabric. Looking down, there was nothing. Which only concluded that Kara -sweet, innocent and oblivious Kara Danvers was blatantly staring at her chest.

“Well, whatever it is,” Lena said almost breathlessly, rubbing her thighs together in reaction. “It’s lovely.” 

Kara’s mouth hung open like a fly-trap for a good couple of seconds over her sicillian sandwich, seemingly forgetting how to eat. She then shoved the entire thing in her gaping jaws in a flash, wolfishly groaning at the taste. Lena’s lips tightened with a threat to smirk and she remedied the growing heat in her office with a manilla folder as a makeshift fan, tugging down her collar a little more to expose the tops of her part breasts nonchalantly.

“I gotta go!” Kara exclaimed all of a sudden, shooting up from the couch as if it was on fire. “Duty calls!”

Interesting… Lena observed as the reporter moved at a nearly inhuman speed to gather up the wrappers on the coffee table and her bag. Lena was lain wake to the downdraft, flushed with the thickening sweet scent. Her ankles wobbled in her heels while rising to see Kara off.

Even the goodbye hug was strangely crushing, lingering with the warmth of each other's bodies. She could have sworn that Kara nosed her hair during the exchange right before they broke apart. And just like that, Kara was gone before Lena could blink.

The rest of the day went on as normal. Business meetings were adjourned and paperwork was finally stacked in their completion on Lena’s desk. By the time Lena had returned home to her penthouse apartment, she sighed with exhausted bliss over a glass of scotch as the day winded down to an end. 

Lena thought about her a lot when she was alone and at leisure. She still could hardly believe that cute little Kara Danvers was the stern and aggressive Supergirl that protected the city. Her golden hair and adorable childlike smile struck a cord at her heartstrings at the very first meeting with her and Clark Kent in her office.

Yes, Lena knew about him, too. Her brother’s obsession over Superman came with prime stalking material within the encrypted depths of Lex’s harddrive. Clark didn’t even reveal his true identity to Lois until he proposed marriage to her. So that made Lena feel a teeny bit better about Kara’s reluctance to come clean about her true identity in the first place. Apparently, Kryptonians had trust issues when it came to the people closest to them. 

And the Luthors were no different.

Lena never told Supergirl, nor Kara, about her experiments with synthetic kryptonite. There was no doubt that Kara would feel betrayed and hurt if that particular secret got out. But she was a Luthor, and Kara was Supergirl. Best friends or not, the dynamic between them would always be complicated. Especially now as Lena had come to realize her ever-growing sexual attraction to her.

She laid wide awake in her satin silk bedding, restlessly tossing while her mind kept obsessing over Kara. Finally, she gave into her secret desires, sliding deft fingers over the taut planes of her pale stomach and lower. God, she was so wet


The next day, Lena spent her time in the lab researching alien DNA and it’s reactions to certain materials. Ever since the destruction of Reign, she was convinced that developing counteractive substances was vital to the protection of humans on earth. There was no telling what would happen in the case of another tyrannic pursuit for complete world domination. So she spent a lot of time preparing for worst case scenarios.

She was analyzing the cellular makeup of various alien species under a microscope when her phone buzzed obnoxiously on the lab table. She ignored it the first few calls until her patience grew paper thin on the eighth. With a click of her tongue, the CEO shot a sharp look of annoyance down at her cellular device when a text message rattled the case.

Alex Davners: S.O.S

That clearly got Lena’s attention. She rose from her place and picked up her cell. Without a beat, Alex’s name showed up on the caller ID on the next call, she finally took it. “Alex!” Lena chirped in the receiver with concern. “What’s going on?”

“I’m sorry to call you while you are at work,” Alex sounded stressed on the other line. “Something is wrong with Supergirl. I was able to apprehend her with kryptonite tranquilizers and bring her back to the DEO but…” The agent took a shaky breath to calm her nerves. “I can’t figure out what is happening. Nothing her blood tests suggest she contracted anything… Lena I’m so worried. I’ve never seen this before and I could use your expertise.”


Lena arrived at the DEO in twenty minutes with careful speeding. Two guards at the entrance leered as she walked into the lobby. Government employees bustled around feverishly in slight panic, precariously trying to focus on their normal work while the problems of Supergirl was at hand. Lena noted that there were more armed men marching around than she remembered before.

“Lena!” Alex looked relieved to see her. “Thank you so much for coming, I know your busy.”

“Where is she?” Lena asked, ready to help with anything that Kara needed. Once the sanitation doors of the medical wing hiss open, Kara’s scent washed over her like a tsunami. It seeped deliciously in her pores which caused a whimper to leave her lips and her heart rate to speed up. She had to grip the edge of the doorway to steady herself in the wake.

“Ugh,” Alex seemed to be taken back as well, nearly gagging at the odor. “Forgot to mention the smell. She’s seeping some kind of stench that makes you want to puke.” Holding her shirt up to her nose, Alex lead the way to another door and opened it with a slide of her ID card.

Supergirl laid unconscious in a hospital bed, strapped down with kryptonite laced cuffs around wrists and ankles with an IV in her arm. Golden hair disheveled and pink skin pooling with sweat. She was still in her suit with a blanket covering her lower half. No doubt that they had to restrain her immediately upon arrival to keep her sedated. And even then, no one had made moves to go near her to make her more comfortable.

“So,” Lena strolled into the room confidently setting her bag of supplies on a table. Seemingly, able to reasonably handle the stench from being exposed to it’s affects over the past week. “What are her symptoms?”

Alex remained by the door, keeping her scrunched up nose covered. “She’s uh…” Her eyes stung and she fought for air to speak. “The smell started to build up dramatically over the course of four days, she’s restless and won’t sleep, now she turned aggressive, almost like a wild animal.” Lena watched Alex’s face turn red on the next sentence. “Also, I noticed something different about her body…” Alex fumbled awkwardly, stepping back with fear filling her eyes. “Under the blanket…” 

Lena drew her eyes over the bundled fabric. Whatever it was, the agent was too distraught to form it into words. With a worried expression, Lena stepped closer to the patient and gingerly lifted the covering.

Her hand snapped back with a shocked gasp, eyes raising up at the agent, completely debauched at what she had found.

“I… um…” The red-head coughed with tears stinging in her eyes, unable to stand the scent any longer. “I am going to contact Superman of any information on what is happening. G-good luck.” She barreled out of the room with the door hissing closed behind her, sealing Lena alone with her kryptonian sister. 

After a long calculated pause, Lena’s curiosity got the better of her.

A hand shakily pulled the blanket completely off, letting it drop to the floor in a fuzzy heap. There stood a tall phallic shape tenting the pleats of Supergirl’s uniform. Lena’s female best friend sporting a rock hard boner, and an impressive one at that. 

With a long moment of staring, Lena popped open the first three buttons of her blouse to air out her increasing body heat. Rearing to get to work, she slipped on a pair of latex gloves, noisily snapping the rubber on her delicate wrists.

She felt around Kara’s neck to check her lymph nodes but found no inflammation. Her blood pressure was high and her heart rate was slamming like a drum to the beep of the monitor. Further into the examination, Lena lifted an eyelid with a light then checked the super’s gums for discoloration. All was normal. But her patient’s canines were extended to sharp points.

Hmmm… Lena felt an odd thrill vibrating through her bones. It’s been a while since she had a diagnosis challenge and she was determined to solve it. Then she started thinking about Alex’s reaction to Kara’s odor compared to her own. While the scent pushed her sister away, it drew Lena in like a moth to a flame. Pheromones?

That hypothesis drew a blush on the Luthor’s face. Within that moment of contemplation, Lena found that her panties had been dampening the longer she stayed in the super’s presence. She had always been attracted to the super blonde, but recently that had been harder to ignore for the sake of their platonic relationship. She deducted that Kara was going through some kind of mating cycle. But it made no logical sense because she was a female. If anything Kara should be going through a heat if that was the case.

Unless Kryptonians exhibit sequential hermaphroditism , Lena amused herself at first, then it made more sense as she thought about it. Aliens came with a plethora of various biological hurdles for survival. Since Kara wasn’t around other kryptonians to mate with, perhaps her body was transforming to repopulate her species faster.

A notification on her mobile phone helped her conclude her suspicions. Alex had forwarded an email she received from Superman and Lena’s eyes grew wider as she consumed the text on the screen.

To Director Danvers:

I never disclosed this information about kryptonians because it is such a rare event that I didn’t even perceive it to be vital for Supergirl to know. What she is experiencing is a second form of maturity. 

Kryptonians have different sets of gender classification. There are Alphas, Betas and Omegas. Most of us were betas like myself -normal male and females. Alphas and Omegas take on more of a mating ritual similar to wolves on earth. Omegas have heats, while Alphas have ruts.

Judging by the information you relayed to me, Supergirl just presented as an Alpha. Alphas are rare in themselves but female alphas are even more so. She will need suppressants to control her urges. If you can’t develop the medicine in time, then she will need to be isolated in a kryptonite chamber for at least three days until she returns to her normal self. She should be experiencing a rut every month, so it is the most importance that you find a solution.

A rutting super alpha can be dangerous to the public.


“Well,” Lena let out a sigh while speaking out loud to herself. “That’s a lot to take in.” And yet, she felt like Superman’s explanation was hardly enough information to go off of. At least she now knows the cause of Kara’s condition. And now she needs to figure out a formula to make a suppressant. “I need to know exactly what I’m working with…”

She turned in her chair, blushing madly at the Woman of Steel in knowing what she needs to do. Other alien species use suppressants for their mating cycles and in order to produce them, certain samples need to be collected, and not the blood kind. Swallowing a growing lump of anxiety, Lena rose from the chair and slowly approached the hospital bed. She could do it with Kara under sedation, but she would never be able to look at her again. No, Kara needs to wake and be aware of what is going on with her own body. Lena wasn’t going to face this embarrassment on her own.

With a trembling breath of encouragement, Lena placed a sample cup on the instrument tray with a tube of medical lubricant. The IV lead from Kara’s arm was pulled out carefully and disposed properly in the hazard materials bin. A groaning whimper escaped the hero, sending an empathic ache in the Luthor’s chest. Poor thing…

“Kara…” Lena called out, soothing a hand over Kara’s shoulder gently. The heart monitor’s beeping picked up pace.

Kara’s eyes snapped open, fully dilated and dazed. Her face twisted in a painful moan, flexing her hands to pull at the restraints. “Fuck…” She hissed and started to become more aware of her situation. Chest heaving, the super started to panic and jerk. “Wha… what happened?!”

Lena looked on her with pity and tried to calm her down by stroking the golden damp strands from her forehead. “It’s okay. You’re at the DEO. Your safe here.” Kara’s eyes finally found her and she sucked in a breath.

“Lena? What are you doing?!” Fear washed over her features while she tried to find a reason on why she was restrained. “What is this?”

“It’s hard for me to explain but… Kara, something has happened to you and Alex called me here to help. I need you to stay calm… Okay?” As she said this, Lena carefully drew a gloved hand southward and lifted Kara’s pleated skirt up.

“WHAT THE HELL IS THAT?!” Kara gawked, eyes wide in shock. The shaft stuck out of her panties, throbbing with a flush of red and pooling a clear pearl of mucus from the tip. “What did you do to me, Lena?!”

“I didn’t do anything." Lena huffed, offended that Kara would assume that she was the one that gave it to her. “You’re an alpha. Do you know what that means?”

Kara sucked in her breaths with heavy sips, jerking violently at the restraints making the bed jump along the tile of the floor, startling the scientist. “I can’t be an alpha! No! Nonono !”

“Kara! Calm down!” Lena pleaded her with panic rising in her own voice. “We’re going to figure out this together. But you need to relax.” The super eventually stopped her jerking, but she still twisted in painful frustration on the bed. Her eyes drew shut with a clenched jaw, choking out a sob as the weight of the news crushed over her.

“You are an alpha.” Lena voiced gently. “There are options. You don’t have to spend your ruts chained up. I can make you a suppressant, but I’m going to… need a sample.”

“A sample of what?” Kara rasped with exhaustion.  Lena gave her a long-suffering look while squeezing a heavy glob of lubricant in her palm, realization struck on her innocent looking features. A gasp squeaked in Kara’s throat. “No! Lena, you can't be serious."

Lena shushed her softly and traced her hand over the hero's abdomen, inwardly appreciating the hard muscles she found there. “I know this is a lot to take in. But if we don't then you will have to be locked up until your rut is over every month. The world can't take that risk, Kara. National City needs Supergirl.” Then with a shaky breath, she adds, “ I need Supergirl.”

The anguish in Kara's eyes told her that she was sorry. Sorry that Lena had to do this. But then those dark blue eyes drew down to cling to the open dip of Lena's cleavage. 

Lena shivered at how lust swallowed up in the darkness of the alpha’s irises. Then, she found a stroke of courage with a watery smirk. “I've.... noticed the way you've been looking at me recently.” Her voice grew thick and throaty, dripping with arousal. “There is no shame in it, Kara. I don't mind… it'll make this process easier.”

The super’s chest rose and fell at a rapid place. “Lena, wait! I don’t know if- Oh! ” Her back arched off the mattress then moment Lena grasped her cock. The girth was hot and heavy, pulsating with the same pace of the rapid beeping of the heart monitor. “ Shiiit…

A gasp clung to the back of Lena’s throat, cheeks flaring with warmth as she allowed her hand to pump Kara’s length at a slow, gentle pace. Her free hand found the railing of the bed to keep from keeling over. Kara’s pheromones had thickened in the pool of saliva coating her tongue and it was in this moment she realized that she was being called to it. As if she were her omega, ready to breed with her.

This doesn’t make any sense to Lena. Kara was a different species, so how is it that she was so affected by it? She fought to stay coherent to her duties for king and country, but it was extremely difficult. I’m going to need to do some more tests about cross-species mating later.

“Lena…” Kara moaned out her name and began to thrust up with every downward stroke. A whimper brewed within her chest at every moaning growl the kryptonian made.

“How does it feel?” Lena asked with a raspy breath, glancing up to Kara’s lust-filled eyes. “Is the pressure okay?”

“S'good,” Kara groaned as she fell victim to her primitive self. “So good. Feels…” Another throaty moan birthed from her lips. “Please… faster .”

Wet, lewd slapping sounds echoed in the room as she eagerly pumped Kara’s cock with more vigor. Lena’s body grew hotter with every stroke, leaving her panting as Kara’s rut was now fully overwhelming her. Liquid arousal overfilled her satin panites and dripped wickedly down her inner thigh. Never in her life had she experienced this much before.  God, what is she doing to me?

Lena’s brain turned into a mushy soup, abandoning all thoughts of reason. She wanted to mount this exquisite alien specimen and collect the sample in a more worthy vessel between her shaking thighs. Such a thought terrified her. Never in her adult life had she ever let that happen. The act was simply too intimate for her Luthor pride.

But this is Kara… Lena moaned besides herself. Simply enjoying this way too much for her own good. And just when she was about to give in, Kara let out a choked sob and gave one final mighty thrust of her hips.


She came like a fountain, shocking the brunette out of her sinful thoughts. Kara’s cock pulsated and jumped as shimmering, pearly jets of seed spewed forth. The plastic collection cup almost flew from Lena’s free hand while reaching for it, but thankfully Kara had more to give. A lot more, apparently.

“Good girl,” Lena praised her with a purr on her tongue, earning a shuddering, puppy-like whimper. She slowly milked the shaft with a gentle massage of her fingers, thoroughly impressed that it overflowed the container to the brim. “That’s it, darling. Wow… you gave me so much.” 

During the donation, Lena noticed something fascinating. The base of the cock was swelling to a large bulbous shape which intrigued the brunette’s curiosity even more. She placed the cup back on the tray to close her free hand around the large swell, testing it with a squeeze. With a broken moan, Kara’s hips jerked again. Impossibly, she was coming more and more. The super suit was laid victim to a white massacre, utterly ruined to the point that no amount of dry cleaning could save it.

“Fuck…” Kara finally collapsed back onto the bed, limp and spent, fighting for air with harsh pulls of breath. 

Raising the cup to the air like a trophy, Lena’s green eyes was enamored. Kara’s come was thick and seem to shimmer with a golden luminescence within the light. Oh, she must see this under the scope.

All thoughts of riding Kara’s amazing appendage were now replaced with her natural urge to analyze this unique sample. Lena hurried over to the medical desk and carefully portioned a drop on a glass slide then slipped it underneath a microscope. Looking through the lens, Lena was shocked to what she found. By her estimated guess, this kryptonian holds well over 900 million per milliliter. Meaning that Kara was over three times more virile than an acceptable human male.

Lena jotted down notes and possible formulas for a suppressant. She will have to get a chemical reading on Kara’s hormone levels later to fully start testing. By her deductions, this may be a six month project. Which could be problematic to the super’s duties to protect the world. After a while, the bed behind her creaked with movement.

“Lena…” Kara called after her in a raspy voice, making her blink away from her work to find that the super was staring at her with a long-suffering expression.

“Oh, I’m sorry.” Lena returned to her side. “I got a bit carried away. How are you feeling?”

“Better… but,” Kara gulped and looked down. Lena’s eyes followed her sight to see that the alien’s shaft was still achingly hard.

“Oh,” Lena’s eyebrows rose. “I, um…” She looked away when she felt heat rising to her cheeks. “I guess you are going to be like this for a while.”

Kara let out a shuddering sigh. “I’m so sorry. If I knew this would happen I would have been more careful. Alphas don’t normally present so late… but,” Kara paused, swallowing thickly. “Ever since… we cleared the air between us. I felt different .”

“I think it’s mutual,” Lena confessed, clearing her throat to soothe the awkwardness in her voice. “Your pheromones have quite an effect on me.”

“I know…” Kara’s voice fell to a whisper, face looking worried with guilt creased in her brow. “I could smell you miles away. It’s been driving me crazy.”

“You’re telling me?” Lena laughed breathlessly. “I’ll do my best to make you a suppressant as fast as I can. But it might take a while, so…” She pulled off the latex gloves and untied her bun, shaking the dark waves of her hair to spill over her shoulders. Then one by one, she unbuttoned her white blouse the rest of the way, revealing a black brassier to Kara’s widening eyes.


“I’ll just have to keep you comfortable for the next three days.”