100 prompts: Rivalry
Words: 1,984 (original) | 4,465 (edited)

A/N: Hooooo boy was this one a treat. Set post-canon, since both the manga and the anime have been driving me crazy and I just want my babies to be happy. I wanted to expand on Eren's inner conflict when I edited this one because I just love getting into this head, and also I wanted more drama lol. More tea, if I may. Because, not gonna lie, Arumika has been so tempting lately. I also totally projected my own deepest desires (lolol) onto their cute, domestic life in this. I hope you have as much fun reading this as I did writing it hehe.

At first, Eren doesn't quite know what to do with this piece of information. He doesn't even think she meant to confess this on accident. It lingered in the air for a bit before he tried his best to swallow it.

Much to the young man's dismay, it turns out Armin is a better kisser than himself.

Or so, that's what Mikasa admitted. The silence in the air was biting, and awkwardness followed. Then came his response.

"Wait, how the fuck do you know this?"

Mikasa looked at him, her face flushed red. She hasn't felt this flustered in front of him in a while. "Eren, please," she starts slowly, "it was such a long time ago."

"I don't see your point."

"Please let it go."

"I think I have the right to know!" he seems so intense and invested in this topic, she finds it kind of cute. At twenty-four years old, this is the most riled up she's seen him in a while.

It has been about a year since the end of the war. After a reasonable number of months spent grieving over their losses, the remaining soldiers were given freedom to choose whatever they wanted to do with their lives. And so, they lived a domestic life in the end. It wasn't something Eren gave much thought to, given the things he was so preoccupied with for most of his life. She was happy, finally getting to settle down with the love of her life after all this time. And he was finally at peace, after calming down and learning to appreciate life around him. It was nice, and it felt right, at last.

They were tired, but finally at peace.

And now that there was no horrible looming threat hanging above their heads, Eren had time and energy to get hung up about the fact that his best friend totally stole his girlfriend's first kiss, once upon a time.

Mikasa hesitated, then she eyed him warily, "as if you've told me everything."

His eyebrows shot upward in surprise. What could possibly be there to know? Instead, he nods in understanding and asks, "What do you wanna know?"

Mikasa didn't expect it, and she hesitates for a moment, but she'd be a fool not to take the invitation. "Well, okay, when we were cadets in training, in the 104th squad, you and Annie-"

"Platonic," he interrupts her easily. "I wanted to learn from her, she was cool, I admired her. But nothing happened," He makes sure to catch her gaze before finishing, "I didn't like her like that. Next."

"Er, okay…" she fought the giddy feeling at his eagerness to please her. Something about knowing what he really thought about Annie, even if it's years later, felt relieving. "What about Historia, when we were part of squad Levi?"

"Historia? Who gets mad at Historia?" he was genuinely confused. "She never does anything wrong, how can you feel threatened by-"

Mikasa raises an eyebrow, now less convinced, and he follows her into their kitchen. "Okay, okay, nothing happened either, Mikasa," the sound of her name and the sincerity in his voice made her soft for a minute. "That whole situation was so fucked up anyway. We kinda bonded over it, I guess."

"I see," she says smoothly, grabbing a cup and pouring tea into it. She picks it up from the top, a habit she picked up from Levi. Eren watches, amused, as he felt a pang of guilt in his chest.

"Mikasa…" he starts, his expression gentle. "I had no idea these things bothered you…"

She chuckled bitterly, bringing the cup to her mouth. It felt really nice finally being open with him when it came to these things. "Well you were so nice to these girls, and so fascinated with them. It just...sucked since you were such an ass to me for a while. And I mean, I was young, so it may have made me feel a little insecure."

'I'm sorry'. It seemed to be stuck at the tip of his tongue. He wanted to reach out to her, to gently stroke her hair and tell her none of that shit mattered now that they were together. That she's the only one now that he's so fascinated with. She looked so stoic, unfazed, but he saw right through her facade. And yet, he couldn't say it.

"So uh, anyone else?" He asks instead, immediately regretting the missed chance.

"You tell me," she says, her hard gaze boring right through him.

"Nope, nothing else," he tells her confidently, and waits until she finishes taking a sip. "Now it's your turn."

She lets the warm liquid go down her throat before giving him a pouty face, "I really don't want to talk about this."

"Why not?" He's riled up again; it's cute, it's harmless. She tells herself she's not just doing this to get a rise out of him. She also has half a mind to just drop it and stop entertaining him altogether. After all, if you ignore the problem, it might go away.

"Because then you get all worked up, and it stops being a civil conversation. Especially since…you know, your history with Armin."

"What, because we fought back in Marley?"

She nodded, hesitantly, reluctant to open up that old wound.

"We're fine, Mikasa. We're still friends," he assured her, genuinely. "That's why he's coming to visit, right?"

"Hmm," she hummed in response, taking another sip.

It was true; in fact, that's how this whole mess got brought up in the first place. They started off discussing Armin's plans to come visit them for the week, then they started reminiscing over childhood memories, which had eventually led to Mikasa revealing that Arming had been her first kiss when they were kids.

The nail on the coffin was when Eren just had to ask if he was any good, and when Mikasa initially said yes as a joke, it was game over.

She was being stubborn, he mused, perhaps he just needed to gently coax the answer out of her (never mind the fact that he just wanted to get close to her).

"Please tell me," he takes a step towards her tentatively, waiting for her to completely invite him into her bubble. She sets the cup of tea down on the counter and turns to face him, enticed by this display of gentleness. Eren pushes a strand of hair behind her ear and lightly tilts her head up to catch her gaze. When her wide eyes told him he had successfully charmed her, he continued, "it's important to me."

"Okay, okay," she gives in almost immediately, blushing, and he smirks. "It happened when we were kids. We were…nine, I think. I had always wondered what it would have felt like to kiss you." A smile tugs at his lips as the discussion takes a good turn. He wants to laugh, and kiss her. But she's still talking, so he waits. "You were so cute and so nice to me, and we were kids. So naturally, I was curious."

Mikasa played with the hem of his shirt, since he was standing so close and she needed something to do with her hands. A small amount of embarrassment was creeping up her cheeks. Then she adds, "but like hell I was going to tell you that."

Eren lets out a chuckle that he was holding back, "Why not? You were a pretty girl, I wasn't blind to that. I don't think I would have objected."

Her eyes narrowed playfully as she jabbed a finger to his chest. "Bullshit. You know how you were as a kid, always pushing me away when I got too close."

"Ah, yeah okay, fair enough," his hand shoots up to the back of his neck sheepishly. He did have quite the fascination with Mikasa for a good chunk of their younger days. He was just far too focused on other things to really give it much attention, and he'd be damned if she ever found out. But he couldn't deny the fact that he had also considered a few times what it would have felt like to kiss her. It ended up being one of those experiences they just missed out on (well, he missed out on).

And now she was telling him that he could have, and probably should have just went for it.

"So wait…so, you asked Armin instead?"

"Yes, hun."

"Why?" he watched her roll her eyes. "You wanted to kiss me, how is that the same thing?"

"Eren-"

"And he just agreed?" Eren scowled at the utter, petty betrayal by his best friend many moons ago, despite it being so trivial and innocent.

"I didn't ask him to do it."

"Okay, so he took 'I wonder what it feels like to kiss Eren' to mean 'kiss me, Armin'."

"See, you're getting mad."

"I'm not mad."

She tried not to laugh; this was ridiculous. "Yeah, I guess so then. Maybe he just assumed I wanted to know what it felt like to kiss anyone, in general. Your nostrils are flaring again."

Eren rubbed at his nose. This time she does laugh, it's cute. Her grown-ass, war-veteran boyfriend was being ridiculous. "Okay, so what made him better?"

This time Mikasa recoiled a little, "I was joking."

"Were you though?"

She thought for a moment, and her hesitation makes him uneasy. "You know I love you, right?" she redirects his incoming attack, picking up her teacup once again.

"More or less," he jokes, wiping some of the liquid from the corner of her mouth with his thumb. She licks her lips and thanks him.

"Why are you being so insecure?"

He's caught off guard for a minute, but when he gathers himself, he allows her to dig into these ugly feelings that were causing the issue to be blown up in the first place. A smile tugs at his lips; she always knew him so well. He takes her free hand and plays with it.

"I guess…I just feel…guilty," he starts off slowly, tracing the scars and calluses on her fingers. "I wasted a lot of time pushing you away, and I know that Armin has always been there for you and with you when I wasn't. It's just adding insult to injury knowing he kissed you first. And apparently you liked it."

"We were kids." She reminds him again. His face falls at the fact that that was her response, and she gives his hand a reassuring squeeze. "Alright, I don't know, I guess he was just so much gentler. Like he was trying to show affection, instead of trying to win a fight against me with his mouth."

Eren raises an eyebrow, his proximity teaming up with his next response to catch Mikasa off guard, "I thought you like it rough. At least that's what it seemed like last night."

He watched her tough expression falter and a mischievous smirk played at his lips. He had her right where he wanted her when she ducked her head ever so slightly to hide the cute blush forming on her cheeks. He sees it as an opening to possibly redeem himself and change her mind; so he leans in to try to kiss her (to prove her wrong, damn it – to show her that he was better and there was no competition at all), but she stops him just in time, suppressing a laugh at his frustration.

"Eren," she reprimands, and he obeys. "Not all of your problems can be solved with more aggression."

When he realizes what just happened, he pouts, "Mikasa…"

"We'll talk later, okay?" she downs the rest of the room-temperature tea and drops it off at the sink as she walks past her devastated lover. "I have to finish cleaning for when Armin gets here."

All he could do was raise an eyebrow, confused, as she kisses him on the cheek and takes her leave.

The first day Armin spends with them was more or less pleasant. Mikasa seemed to be genuinely enjoying his company as they sat down to catch up on life. But there was something heavy residing within Eren, weighing down his shoulders and his smile.

He did miss Armin, and his presence was something nice. It would be such a waste to let this go to shit just because Eren was feeling a little petty and hurt.

"Hey, uh...can we talk?" Eren stands at the doorway of their guest room later that night.

"Oh, hey," Armin looks up from the book he was reading, "what's on your mind?"

Eren steps into the threshold of the room awkwardly and Armin immediately understands something is wrong. "I wanted to ask you something."

"Okay, shoot." He puts the book down to give his undivided attention.

He takes a deep breath before starting slowly, "back then…when you kissed Mikasa…" At this, Armin's eyes went wide, looking like a deer caught in headlights. "Yeah, she told me. What was that about?"

"Uh…" he seemed at a loss for words as his best friend just stared at him, his expression unreadable.

Eren sensed the emotion clouding Armin's thoughts. "I just want to know. I'm not upset or anything."

He didn't buy it, but nevertheless relented, knowing there was no way out of this. And even if escape was possible, there was no point. He deserved to know. "Alright, um...it was just a really bad time, Eren. Things were going to shit left and right. She lost Sasha- one of her best friends; it really messed her up. Levi was dying, and you were...being a real piece of shit."

Eren's expression changed drastically, a mix of confusion, surprise, and hurt fighting on his face. He kept quiet, not knowing what to say.

"Our time in Marley was truly a low point; she was vulnerable, and I guess I was too. It just...happened."

"What…" Eren seemed to find his voice, but his thoughts were still everywhere. Suddenly, images of his two best friends played in his mind: Mikasa, vulnerable, hurting, broken from his mistakes. Armin, confused, angry, touching her, holding her. He must have been gentle and careful too, that's just how Armin is. Why was she with him again? Suddenly his heart was in his stomach, dissolving in the acid of his regrets. He shakes it off and returns to reality. "What are you talking about?"

"Is...is that not what you asked?"

"I meant when we were kids." He sits down on the bed beside him, his legs unable to support him properly at this point. It hurt.

Armin pauses, remembering the correct memory, and he felt foolish, "...ah, fuck."

"What the fuck, Armin?" Eren seemed to have regained consciousness.

"Hey man, relax," He throws his hands up in the air in surrender, reading the hurt on the Titan shifter's face, careful not to poke the bear any more. "Like I said, we were just...in a really weird place, okay? It meant nothing, to me at least. I guess."

"You guess."

"Dude, what do you want me to say? Will it be easier if you tell me what you want to hear?"

The two seemed to have reached an impasse, as Armin didn't want to get any more aggressive and Eren realizes this wasn't the right way to deal with this. The eye contact was intense enough to halt the world into a standstill. The latter takes a deep breath to calm down. A moment passes.

"I'm sorry," he reels back. "It's a stupid thing to fight about. It's not...worth losing your friendship, again."

Armin's face softens, "I'm sorry too, Eren. If I knew it would hurt you later on I wouldn't have done it."

"It's...okay." he says, not sure how else to respond. Then he asks, a little hesitant at first since he knew what he was walking into, "is that all that happened between you two?"

"Yeah," it was an honest answer. Yes, they were close, but it never amounted to anything else with Mikasa's heart elsewhere and the circumstances they were in. "But, if I may, why does it bother you so much?"

Eren laughs sourly. "You've always been better for her," he explained simply.

"Come on, man, that's not true."

"I just don't know if I can ever make up for everything I've done," he completely disregards the comfort that Armin tried to give. "You, on the other hand, have a clean slate with her."

It was quiet for a few minutes, as they both gathered their thoughts. The silence wasn't painful, however, something about sitting in a comfortable silence with Armin in the midst of his issues was reassuring.

"That sounds like something you need to address, with yourself." He watched the expression soften on his best friend and took as an invitation to continue. "She loves you, Eren. She always has. You can't undo your mistakes in the past; all you can do is move forward, and you're doing just fine. Besides, the best apology is changed behavior."

Eren seemed to be digesting his words, resulting in a warm smile. "I hate that you're always right."

"Yeah, I still got it." The air seemed much lighter. "Be gentle with her. She deserves to be treated right."

"I know." He stands up and rests hand on Armin's shoulder affectionately. "Thank you."

It seemed pointless to get angry about it, so Eren resolves to just show her. After all, actions speak louder than words. He walks back to their shared bedroom, just thinking about what Armin had said to him just moments ago. He finds her on the way to the room as well, a full laundry basket in hand.

"Hey," he stops her. She looks tired- it's late at night- but her eyes brightened at the sight of him.

"Hi," she smiles, walking into the room with him. He lets her set the clothes down, and then takes one of her hands in his to pull her closer. His other hand reaches up to cup her cheek, brushing some loose strands of her long hair that had fallen out of the ponytail, out of her face.

Mikasa felt her heart stutter at his actions. Even a gesture this simple was enough to send her up to cloud nine. He loves her, she knows, but being Eren (touch-starved, socially awkward Eren) meant he showed it in his own ways. She never objected to his methods - most of the time this meant nights filled with so much passion and intensity that she'd wake up the next morning wondering if all that was just a dream. That, and little favors he would do for her that just defined domesticity between them and their lives now.

He never really noticed that their relationship was this intense, hot fire that burned brightly all the time. He realizes that ever since they got together, they've just been going at it to make up for lost time. Perhaps it wouldn't hurt to dim it a little to make a small, comforting fire to keep warm and cozy. At some point it wasn't even about proving his point about Armin anymore, and one-upping his best friend. He needed her to know how he felt about her, more than anything. He wanted to show her that he was just as capable of being gentle and sweet, for her.

There was no need for any other words; he was determined to show her that he was serious about earlier. So when he was absolutely certain that she had completely succumbed to his charm, Eren tilted his head and leaned in just enough to catch her lips.

Just like that, everything else around them had disappeared to Mikasa. The clean laundry that sat by their feet and the fact that Armin was just in the next room was forgotten. It was only her and Eren, the young man she had loved practically all her life.

She leans into him eagerly, attempting to close the distance between them, but he pulls back just enough to keep her from deepening their kiss. In response, a small sound of displeasure escaped her throat, earning a cheeky smile against her mouth.

He kissed her slowly, but so full of confidence and love, that Mikasa almost felt light-headed. She felt every little movement of his against her, sending goosebumps up her arms. It was ridiculous how much he affected her, not that she was complaining.

The hand that cradled her face found its way into her hair, and when she took this as a go signal to get closer, he shifted his other hand to her waist to control the distance once again. She let out a small gasp in response, leaving him an opening to deepen the kiss, at his own pace.

Eren tilted his head slightly, smirking at how he knew how much control he had over the situation. He couldn't help but feel so smug that the mighty Mikasa Ackerman was pretty much wrapped around his finger at this point. When his name escaped her mouth in a quiet, desperate manner that almost drove him over the edge, he decided it was a good time to ask.

"Better?" He pulls back, looking straight into her eyes. His gaze was so intense, it was almost intimidating. He held her so gently though, it didn't match the way he looked at her so fervently. Mikasa is caught off guard, and couldn't find the words. Instead, she nods, helplessly. "Hmmm, not good enough, Mikasa," he teases.

She tries to frown, "what do want me to say?" Her voice is soft and breathy, clearly hungry for more, and it sent a heat down through his stomach. He had to keep his cool though, this was his turf.

"Tell me I'm better than Armin."

Oh, there was no doubt about it, Mikasa knew. As sweet and comforting as Armin was to her both times, it just didn't send sparks and warmth through her whole body the way Eren did. But there was no way she was going to give him the satisfaction that he so much needed. Especially when he was just being so petty.

"Eren, don't be ridiculous."

"Yeah, I knew you'd say that," he says lowly, and she almost yelped as he dives in again.

He gives her a little more control this time, allowing her to wrap her arms around his neck to pull him closer. He felt just how much she needed him, and it was getting more and more difficult to hold back just to prove his stupid point.

It didn't matter, he just had to outlast her and have more self control. He opens his mouth a little to graze his tongue against her closed mouth gently, and she accepts the invitation. She was making his legs feel like jelly and his insides were all warm and fuzzy. He wondered how he ever let all his teenage years go by without kissing her before, and he realizes he really couldn't blame Armin for wanting this.

"Say it," he prompted, and it almost sounded like he was begging. Eren's voice was low and husky, and it was clear he was losing his cool. She smiles wickedly against him in response. He pushes forward a little bit, and she gasps sharply as she trips over the laundry basket, pulling them both onto the bed. Mikasa giggles, her soft laugh was music to his ears.

He doesn't waste another moment though, diving in to trail kisses from her mouth and down to her neck, now that she was pretty much cornered beneath him. One of his hands was tangled in her hair and the other one had snuck into her shirt, working its way up. Mikasa moaned softly at his touch, sending chills down his body and calling him back up to her lips.

He looks down at her, and she just looks so delicate. For a second he forgets how this all even started. Instead, he says the first thing that comes to mind, without thinking.

"I love you," he blurts out, caught up in the moment, "and I'm sorry."

"For?"

"Everything," he leans his forehead against hers affectionately, careful not to crush her with his weight. The way he's holding her explains exactly how he feels about her and makes her heart flutter.

"I love you too," she tells him, her eyes sparkling, and all of a sudden all his previous insecurities seemed so stupid. She pulls him down again and he doesn't object. His newfound realizations fueled the heat between them this time, and the next thing they knew, their hands were everywhere.

She moves to undo his belt and suddenly Eren remembers what initiated all of this in the first place: she still hadn't said what he wanted. He pulled back abruptly and she looks up at his eyes clouded with lust.

"Eren," she tries to scold him for denying her right before they got to anything interesting, but she just looked like an angry bunny to him.

Eren laughs a little, surprised at her reaction and is actually taken aback a little; she actually cracked before him! He reels back, teasing her with a shit-eating grin as he watches, amused, at how utterly flustered she looks: cheeks red, panting heavily. Mikasa's hair was sprawled on the bed, her shirt was halfway off, and her chest rose and fell as she tried to find words.

If this kid wasn't so stubborn, he would have given in long ago. But this was Eren Jaeger, and he really wasn't going to give in until he got what he wanted.

"Fine," she growls when she realized it. He doesn't need to ask again. "You're better than Armin."

"Thank you," he breathed, finally at peace, and moved in to finish what he started.

They didn't notice their third musketeer come in, a blanket draped over his shoulders as he stops at the doorframe to tell them to be quiet (the damn walls were so thin, he sighed, it interrupted his late night reading).

"Hey guys," he greets casually, not even caring that he clearly (deliberately) interrupted something.

Mikasa looks surprised, her head snapping over to him. She's at a loss for words, flustered as her lover's hands were so far up her shirt and she was centimeters away from unbuttoning his pants. Armin fights the urge to laugh as his best friends looked like deer caught in headlights, and briefly wonders if this was his doing. Eren drops his face onto her shoulder, unable to face his best friend, ears heating up.

Armin raises an eyebrow, tongue in cheek, "better than me at what?"