Chapter Text
Being a hero and saving lives on a daily basis were the most rewarding things Kara thought she could ever do with her life. But that morning, as a quick glance to the obnoxiously bright phone screen that had shook her awake showed 3:03 a.m, she regretted some of her life choices.
Only her wavering moral code could force her to even consider answering a call this soon after coming back from a week-long mission. She had punched her way through waves after waves of stupidly incompetent criminals that just didn’t seem to know when to quit, and she now believed she deserved at least a good night of sleep.
The phone went silent, stopping its vibrating journey across the bedside table for only a moment before a second call had it moving over the edge and towards the floor.
Kara caught it midway, having finally made up her mind to answer.
Alex’s apologetic voice resonated into her ear in a way that Kara recognized immediately. The words barely registered in her mind as the tone of them warped until it was nothing more than low humming against her skin. Heat slowly pooled into her lower belly and an all too familiar hardness began to push against the soft fabric of her pajama pants, bringing with it a hunger that could never be sated.
“Kara, can you hear me?”
“Sorry, I was asleep.” Only in these circumstances, did Kara give herself enough leniency to lie. “I can’t come back, I need to rest.” Anything was better than the truth.
She hung up before Alex could respond, as there was nothing she could have said that wouldn’t have been picked apart and twisted in every direction, until it was nothing more than fuel for the fire steadily taking over Kara’s mind.
Of course, she called again. Kara could almost hear her worry over the ringtone, but she couldn’t find it in herself to pick up. Blocking out the fantasy of Alex coming to check on her in a scene that would put any porn intro to shame, was hard enough a task to justify ignoring her for a moment.
Two missed calls later, her phone screen finally turned off, bringing back the darkness into her room and allowing Kara to easily hide the guilt that came with the scenarios her mind would come up with to help her appease herself.
She didn’t even know why she bothered to try and resist anymore. Ever since she had turned 20 and learned the hard way that being on a different planet didn’t make her any less of a Kryptonian, she would end up in the same position every six months or so. Safely hidden under the privacy of her blanket, powerless and trying to reason with herself until the next morning, where she would predictably run out of will and give up the reins to the most basic of her instincts. The few following days would be something of an arm workout as she did what was necessary for the problem to go away, and by the end of the week, everything was usually back to normal.
After her first few ruts, it had taken Kara a month to be able to look at Alex in the eyes again. No matter how hard she had tried, her mind would always come back to images of Alex or the sound of her voice, and gradually less and less appropriate things about her, until it was all Kara could do but to moan her name into a pillow.
And this time didn’t feel like it would be any different. The only change since her last rut was that she now spent most of her time flying around town as Supergirl. And up until now, the fact that twice a year she would spend a week without powers consumed by the need to bury herself deep inside of Alex, never seemed like it could become a problem.
She could feel herself getting harder between her fingers as she laid on her back, pants halfway down her thighs and quickly stroking up and down her dick with both hands. She briefly thought about taking off her shirt as it was always easier to clean the mess she made off of herself than out of any fabric, but the prospect of a fast approaching orgasm immediately corrected the course of her wandering mind.
In the haze of the first of many climaxes she would have that day, the knock at her door startled her back down to earth quicker than her pod ever did.
“Kara, I’m coming in, okay?” Alex’s key was already inside of the lock when the last of Kara’s brain function finally came back to her.
In one swift move, she put her pants back up and jumped off the bed. She grabbed a pillow on her run towards the door and opened it just enough so that Alex could see she was fine.
“Kara, what happened, are you okay?” Her eyes went straight to the pillow Kara kept pressed against the front of her pants in a desperate attempt to push back the inevitable.
“I’m sorry, I fell asleep,” She wished she was better at lying, “I’m just really tired, can we talk tomorrow?”
She closed the door after Alex hesitantly agreed, and rested her head against it to listen to the footsteps getting away. The sound of the elevator closing was all the confirmation she needed that there was a safe enough distance between them for Kara to get back to the matter pressing against her pillow.
There was something pathetic in what she could imagined was the scene around her before she opened her eyes the next morning.
She had only made it as far as the couch before the hint of Alex’s perfume that lingered around had gotten her so hard that she could barely walk. She’d then spent the rest of the day either lying on or around the ruined piece of furniture, taking care of herself.
The days that followed weren’t much different than this one, save for the brief call she gave Alex to explain the much more plausible lie that she had solar flared on her way home, and couldn’t possibly get out for a few days. She even made sure to call her once a day after, when her condition allowed a few minutes of peace, to reassure her that she was okay and absolutely didn’t need her to come over.
——-
Six months after Kara exhausted herself fighting a group of amateur criminals, Alex realized that every new enemy that came their way would make her increasingly attentive to Supergirl’s every need.
Not that she needed an excuse to want to be there for her foster sister and best friend. She just couldn’t shake off the idea that something was wrong, even if exhaustion was the most plausible explanation. The entire month before the incident had been abysmal, with rogue aliens and wannabe supervillains trying their best to take over the city.
So Alex did her best to try and focus on the fact that their relationship, now being the closest it ever had been, was reason enough to believe that Kara would definitely come to her if she had a problem.
Kara <3 - Sorry I can’t come to work today, I really need to finish this article. I’ll text you when I'm done. (7:05 a.m.)
It would have been one thing for Kara to miss one day, her schedule management skills had only gotten worse since she started spending her nights saving the world. But after three days of Alex’s calls only being answered by vague texts about deadlines, it was all she could do but to go and make sure Kara was okay.
A quick stop by, with an armful of donuts and pizza for lunch, would be the perfect way to apologize if it turned out that she had actually bothered her while she tried to work.
Half an hour later, she got into the elevator and managed to press the button for the right floor without dropping anything from the mountain of food that remained secured in her hands. Even the brand new sheet covered couch that stood a little further in the way than the old one, begging to be run into, didn’t prove to be big enough of an obstacle for Alex to lose her grip.
And yet, a moment later, with half of a pizza settling on the top of her shoe and an array of pastries flying around her, she could barely keep enough focus to stand up as she watched Kara come out of the bathroom in a state of nakedness she had never seen before.
She stayed frozen, unable to look away until Kara finally managed to grab the nearest bath towel and cover herself. “Alex, why are you here?”
Let it be known that if Kara hadn’t spoken first, Alex had all but made up her mind to just leave and pretend nothing had ever happened.
“I brought food.” She gestured around herself, presenting the mess she had just made.
The absurdity of the scene wasn’t enough to lightened the mood, and Kara only got more agitated with each second that passed. Her breathing was fast and her arms were clenched tight around the towel while Alex had to actively keep her eyes from drifting down Kara’s body and get a full view of the tent slowly getting pitched under the fabric.
“So…” She had hoped she could come up with something to say, but the million questions battling in her mind probably wouldn’t have been helpful in this situation.
She settled for the next best move and bent down to grab one of the donuts that had landed next to her. She ate half of it silently, keeping her mouth occupied on her way out of the apartment and into the elevator. Chewing loudly on the ride down with her eyes wide but unfocused, she couldn’t decide what she wanted to fixate on first. The appendage that definitely wasn’t there before was hard to ignore, but the effect she seemed to have on it kept messing with her train of thought.
Thankfully, her phone rang before she could get too much into it and she picked up hoping that something big enough had come up at the DEO that it would keep her brain occupied for the next few years.
“Alex, can we talk about this later?” She absolutely hadn’t expected to hear from Kara while she was still in the building. “I’ll explain everything but this is gonna have to wait a few days.”
Days?
“Sure.” Alex answered with a tone so casual, you could barely tell she wanted to run back up the stairs and get those answers now. “But you’re okay, right?”
“Yes, I’ll call you back when it's over.” She hung up before Alex could ask what would be over?
Five days passed rather slowly before she was finally back in Kara’s apartment. She uneasily sat on the couch, wondering why the sheets were gone and why they had even been there in the first place, while Kara got her a drink.
The conversation didn’t seem to organically want to go where they needed it to be. Alex caught her up on everything that had been going on at the DEO in the past week, and Kara followed by getting into a passionate monologue detailing the tv shows she had binged while stuck at home.
She was halfway through the final plot twist when she apparently decided that this was as good a time as any to jump into it, and changed subject without finishing her sentence.
Alex remained silent, trying to process every information recited to her in a manner that was not unlike a school presentation.
The concept of a dominance hierarchy and the rules surrounding it that were enforced on Kryton to not only guarantee descendants for their people, but also solidify the archaic system making sure only the strongest and most dominant people stayed in charge, wasn’t all that surprising to her.
The female alphas growing a penis when needed so they could also make said descendants, was a bit more of a question mark, but nothing a scientist such as herself couldn’t understand.
The one thing that bothered her most was how on earth could Kara have hidden all of this until now? She was a terrible liar at best.
“It only began when I turned 20.” Kara explained, “I refused to tell Eliza and ended up calling Kal, thinking that it would be less embarrassing.”
Knowing her cousin, Alex knew that it certainly wasn’t.
Becoming Alphas was kind of inevitable for the house of El and Kara had had time to be educated on the subject before she left the planet. Kal, on the other hand, had to learn about it from asking Kelex some really uncomfortable questions.
“Since humans only produce a fraction of the hormones an average Kryptonian would, we weren’t exposed to enough of it to present when we were teenagers as we should have.”
Which was why Kara had begun to think that she simply wouldn’t present at all as she grew older. She even dared to believe that she was lucky enough to be a beta.
A deep blush crept up her neck and she looked slightly away from Alex before continuing, “Anyway, the important part is, every six months or so, I lose my powers and get an insurmountable urge to…” she tried to make a gesture with her hand but abandoned half way through it, “You know.”
Judging by the shade of red Kara’s face turned into, it was safe to assume that she had seen the exact moment where Alex figured out exactly what she spent the week doing everytime this happened.
“It's not supposed to last this long.” Kara said quickly, “But since it isn’t getting what it wants, it's only getting worse over time.”
The awkwardness of this conversation wouldn't go away for a few weeks, but just like any other obstacle in their relationship, they would eventually find a way around it.
Soon enough, Alex could find it in herself to ask small questions here and there, which Kara always seemed happy to give an answer to, and the next few months went by without her even realizing it.
Sure, everything she had learned about Kara was extraordinary enough that it should have at least stayed close to the front of her mind for a while, but with the life they lived and the challenges they faced almost every day, it was understandable that she didn’t keep track of the exact countdown before the next rut.
Which is how Alex found herself driving a powerless Supergirl back to her apartment one night, making sure they weren’t followed by one of the many witnesses to the girl of steel’s show of dominance at a dive bar.
Kara’s overreaction to someone interrupting Alex mid-sentence to ask her if she wanted a drink, had been to throw a stool across the room and straight into a speaker, prompting a group of angry aliens to join in on the action and try to get Kara out of there.
They were pretty lucky that her powers had gone away before she hurt any of them, but enough damage had been done to the bar for the owner to call in the big guns, which was why Alex ended up breaking every traffic law she knew on her way to Kara’s apartment.
She promised to take care of everything before running out, leaving Kara safely curled into a ball on her bed. But to say that she was unsuccessful would be an understatement.
The next day began with a group of aliens trying to take over the DEO building, demanding that Supergirl be brought to them for reparation. And for every one of them that the agents could arrest, two more seemed to come out of nowhere as replacement.
By nightfall, Alex had run out of excuses as to why Kara couldn’t show up, and even if Jon had assured her he would never read her mind without consent, her last few lies were shaky enough for her to doubt that he wouldn’t just decide to get to the truth.
Who would have thought that her first ever phone call to Superman would be to talk about something like this?
“Is there any way we can make her rut go away faster?” She quickly asked, proud of how casually she had managed to say this. “I know this is awkward but we’re in a bit of a situation and this is getting ridiculous.”
Kal took a few seconds to answer, “Assuming that she hasn’t found a mate yet,” He cleared his throat, “She’s probably desperate for any attention.” It was painfully obvious that his first conversation about this with Kara had been nothing short of a nightmare for him, “Pretty much anything could help at this point, if you… uh.. know what I mean.”
She did know, but she had foolishly hoped for a different answer.
She hung up and looked around herself to make sure she was still alone in the locker room she had deemed a private enough space for such a conversation, then quickly taped Kara’s name on her screen before she could change her mind.
The phone rang until voicemail once, then twice and on the third call, Kara finally answered.
Alex didn’t wait for her to talk, “Just tell me what you need, Kara.”
“I can’t- I won’t tell you that.” She was out of breath.
“Kara-”
“I need you, Alex.”
She had asked the question, she should have been prepared for the answer. Of course Alex knew that, in this state, she would have said that to pretty much anyone, but this reasoning didn’t stop her heart from skipping a beat at the mere thought that Kara could want her like this.
“You have me.” It was way too easy for Alex to say that, “You know I’m all yours, right?”
A moan, unsuccessfully muffled into what must have been Kara’s pillow, carved itself straight into the darkest corner of Alex’s mind. “Just tell me what you want.” And she needed to hear it again.
Kara groaned directly into the phone this time, “Rao, I want you so bad-” She hung up.
A couple of agents running down the hallway startled Alex enough to get her up from the bench. The sensation of having been caught doing something she shouldn’t have, and desperately wanting to do it again, almost got her to hide in one of the stalls. She rolled her eyes at herself and sat back.
The TV hanging from the ceiling in the corner of the room playing the 24h news, caught Alex’s attention as a picture of Supergirl filled the screen. The speakers had given up a long time ago, but the subtitles let her know that there was now coverage of the attack going on just outside of the building.
“A group of rebel aliens have made it their mission to infiltrate this National City building and the apparent paramilitary group currently occupying it are refusing to give any comments. The attack has now been going on for more than 10 hours without any intervention from Supergirl, leading the public to wonder, where is the girl of steel? Back to you Rob.”
Kara called her back.
“Alex, I-… Can you just talk to me? Say anything.” Her voice was low, barely audible through the music from the news channel in the background.
“You don’t have to do this," Alex couldn’t shake off the guilt, "I’m sorry I made you think that you did. We’re gonna be okay here.”
“I want it to stop!” A painful groan followed Kara’s answer and finally broke Alex.
"Then come and take me.” The words left her mouth faster than the time it took to realize she had said them out loud.
The shift in Kara’s breathing was instantaneous.
Alex knew she was bad at this, she didn’t have much experience in phone sex, and the idea that it was Kara who she would say those things to made it harder than she expected. “If you were here, I’d-”
“If I was there, all you’d be saying is my name against the wall.”
Oh. This caught Alex off guard enough that she didn’t immediately notice that Kara had hung up again.
She stared at nothing for a moment, mouth slightly open, trying to come up with a response she could be able to live with. The heat that had pooled between her legs came up with some answers of its own, but those would have certainly been crossing a line that Alex wanted to pretend was still in front of her.
She shook her head in an attempt to get her mind out of her pants and back into the world, stood up and went back where she was needed.
An hour later, Supergirl flew in and joined the fight, visibly tired. Her hair was a mess and she had opted to wear sweatpants on top of her usual red skirt, which made Alex crack a smile.
It didn’t take long before Kara stopped flying and took a few punches, prompting Jon to order her back inside for a break.
The look in his eyes, paired with the slight tilt of his head as he stared at her, confirmed to Alex that she would have a lot of explaining to do later.
——-
Kara almost tripped as she landed from the weak flight that didn’t get her further than the edge of the balcony. This was ridiculous. She had hoped that getting herself off to the sound of Alex’s voice would be enough to satisfy her rut. It was by far the best material she had had since the one time it started while they were getting ice cream.
Sure, even after getting beaten dry for an hour straight, her dick was still there. But she had no way of knowing how long it actually took for it to go back in after what she assumed was her first successful rut.
But a single sight of Alex, standing on the DEO balcony with her eyes locked on her and a subtle smile, proved to be the key straight into her obsessed brain and before she knew it, her powers were dimming.
When Jon ordered her back in, she didn’t even pretend to object. As soon as her wobbly feet touched the ground, Alex grabbed her arm and led her toward a locker room at the far side of the building.
She could feel in the vice grip around her wrist that she was about to get an earful. The fighting without powers, the phone call, the borrowing of Alex’s sweatpants, there was no getting out of this one.
Refusing to lose the last of her dignity, Kara fought with everything she had in herself as her dominant side tried to take back the reins. If there was one thing she was sure of, it was that she would never let her alpha talk to Alex again.
She leaned against a wall, preemptively biting her tongue to keep from making the situation worse.
Alex locked the door behind them and stood in front of her for a while, arms crossed and seemingly expecting her to say something. But before the tension around them could get the best of Kara’s resolve, Alex dropped to her knees and took the sweatpants down with her, her eyes darkening at the sight of the bulge barely hidden under the skirt.
The real Kara, the one that didn’t use her dick as a brain, wanted to say something. Anything. This wasn’t how she wished this would go down. For all those years she had spent hoping for the perfect moment where she would be able to tell Alex how she really felt about her, this wasn’t it. It was lightyears away from what she thought Alex deserved.
But this moment, which could have been plucked straight out of her fantasies, was everything the alpha in her had ever wished for, and there was no stopping it.
When she finally felt the warmth of Alex’s tongue against her skin, Kara instinctively stopped breathing as she tried to keep from coming right then and there. The slow drag of lips down her shaft, coupled with the tracing of a tongue under it, made her believe that nothing would ever feel this good again and she knew just how pathetic this sounded.
Alex pulled her head back, taking her sweet time while the feeling of her mouth imprinted into every corner of Kara’s soul, and caught her breath before picking up the pace.
It didn’t take long for Kara to abandon all semblance of control and put a hand on Alex’s head, her fingers quickly finding their places into red hair as she gently grabbed a hold and began to roll her hips.
The vibration of Alex’s approval against her was all the encouragement she needed to keep going. And after what could only have been a minute of the pure bliss that was fucking into Alex’s mouth, Kara was already about to lose it.
“I’m gonn-”
Her attempt at communication quickly turned into a moan as Alex managed to finally take all of her into her mouth and down her throat.
She silently came, bent halfway above Alex’s head, with a last shaky thrust as Alex swallowed every drop of her.
This was nothing short of an out of body experience that Kara only wished she could have observed from a far, committing every detail to memory before getting back to the reality that there had to be an explanation as to why Alex had let herself be used in this way, which Kara didn’t want to know.
She eventually straightened up, battling the urge to get a taste of herself on Alex’s tongue, and waited for her to say something. She kept her eyes on the floor until a cellphone resonated through the room, reminding her of the situation they were in.
"Yes, I’m on my way, sir.” Alex answered, and just as quickly as she had spun Kara’s world upside down a few moments ago, she left.