Disclaimer: I don't own Shingeki no Kyojin

Author's Notes: Okay, I did not expect so many reviews for this beyond depraved piece of smut. But you people are fantastic. I love you all so much, in an entirely non-creepy way. I'm sorry for all the angsty Eren and for torturing the poor boy, and Mikasa. It'll continue for 1-2 more chapters, all this, till they finally have their OT3 time. Yay.

It made me smile the way some of you were siding Eren and Mikasa last chapter. Frankly, I felt sorry for the both of them, it's all just a very messed up situation. Which will soon get resolved. And then everyone will be happy.

Warning: Rated M for sMut, as usual. This chapter contains LeviEren or Riren towards the end. You have been warned. I'm really sorry if that bothers anyone/makes me lose readership. But from the outset, this was an ot3 story (with a mix of all three of the in their respective couple ships or whatever you call them) so I'm trying to stick to that and make it work.

Fraternization

Chapter 3: Corporal

For the next few days, Eren pretty much ignored Mikasa completely. It wasn't hard given that they had entirely different training regimens.

Mikasa's consisted of her training privately with Rivaille. It boiled Eren's blood just thinking of it.

Her words from before echoed in his head.

'I'm in love with you. I always have been, for a long time.'

But then there was still that image of her, entwined around Rivaille, imprinted in his mind.

Eren clenched his fists, eyes stinging at the memory.

Mikasa... how could you?!

"Lighten up."

Mikasa glowered at the man.

"Fuck you, heichou."

"Not when you're so depressed. You wouldn't be much fun."

Mikasa wanted to pounce at him then, and pound him to the ground. He stood there, infuriatingly calm, his arms crossed as he watched her swing through the trees, cutting down wooden Titan after wooden Titan.

"This is all your damn fault!" she seethed.

"My fault?" he raised an elegant eyebrow at her. "I admit, locking the door would have been a good idea. But other than that, you were as much into it than I was, if not more."

Mikasa hated him at that moment, hated him more than she ever had. He hadn't made a move to touch her, ever since Eren had walked in on them. A part of her wanted him to, just so that he would get close enough for her to scratch his eyes out.

Her heart ached as she thought of Eren, and his betrayed, shocked expression.

"Eren... I'm so sorry..." she murmured aloud.

She flew through the air, whirling around as she sliced down more Titan cutouts, landing gracefully on the ground in front of him once she finished off the last.

Mikasa sheathed her blades. Levi looked unimpressed.

"Again."

"What?!"

"That was pathetic. Too slow. I got bored watching you. Do it again."

Mikasa's lips curled back in a snarl, and it took every ounce of her self control not to attack him instead. She turned around and shot back into the air, attempting the course for the fifth time that day.

"DIE! DIE YOU FUCKERS!" Eren raged as he sliced through the Titan's neck with two parallel cuts.

It had been a few months since the Castle Utgard incident, and Titans wandering around within Wall Rose was no longer unheard of. That day, a group of them had converged around the Scouting Legion's headquarters.

"Eren, you moron!" one of the scouts called. "Get back here! Heichou's orders were to keep you inside and safe! Let us deal with them!"

Fuck Heichou and his orders. Both he and Mikasa treat me like I'm a kid. They think they're the only ones capable of killing all the Titans, and -

"Tch," Eren spat, gritting his teeth as he swung over another Titan's shoulder, hacking viciously at it's neck.

Once that was one was down, he shot into the mass of Titans that was gathered near the stables, managing to bring down another three, despite the yells of his squad members.

It was too late when he noticed the large hand looming over him.

"Eren!" someone screamed.

"You bastard," Eren choked out, as the hand squeezed. He bought his thumb to his mouth.

He knew he wasn't in any danger. He'd transform and crush them, crush them all. Rushing headfirst into such a large crowd of Titans without enough trees or buildings around for leverage was suicide for anyone on 3DMG, no matter how skilled. But Eren knew he could do it, with his powers.

But before he could bite his thumb, there was a blur of color and a flash of blades. The hand around him dissipated away, and Eren immediately shot his 3DMG hooks out, propelling himself away from the mess momentarily.

He spun around midair to look for his savior, and saw Mikasa spinning around furiously, cutting down Titan after Titan.

A spasm of fear shot through him.

That idiot! What does she think she's doing?!

Eren jerked himself forwards, shooting towards Mikasa, but a hand tugged at his jacket, pulling him backwards.

"What the fuck-"

Eren turned around, his angry eyes meeting the narrowed ones of the Lance Corporal.

"Eren. You're supposed to be in the castle."

"Don't fucking tell me what to do! I'm killing the bloody Titans! And right now Mikasa is -"

"You trying to save her won't solve anything. She'll just try to save you all over again and you'll both be in deeper shit. Stupid brats."

And then without a backwards glance at Eren, Rivaille flew into the rabble of Titans at lightning speed. Eren could barely follow his movements, but somehow he managed to grab Mikasa and extract her from the mess, meanwhile cutting down at least five or six Titans himself.

Rivaille released her when they had reached a tree, the very same tree Eren was now standing on. He all but dumped her on the thick branch. Mikasa glared at him.

"Both of you little shits need to learn to follow orders," Rivaille snapped at them. "Mikasa, use your brains for once and stop running after Eren every time. He's an impulsive idiot who will get himself eaten, but unlike you, he can transform and regenerate. And Eren. Get back to the castle now."

Eren threw one last dirty look at Rivaille, ignoring Mikasa completely, but obeyed, and sped back to the castle.

"Eren - " Mikasa called after him, but stopped with Rivaille gripped her shoulder tightly.

"Now's not the time. Focus on the Titans."

"But - "

Rivaille sighed.

"He doesn't hate you. He was all ready to jump to your rescue right now, and would have if I hadn't stopped him. Now stop crying like a fucking baby and do your duty as a soldier."

Fuck him. Fuck him! If I was a Titan I probably could tear him to pieces.

Eren paced through his little underground room, his hands fisted by his side.

Sometimes, he really wanted to punch Lance Corporal Rivaille hard across the face. Off late, ever since the incident with Mikasa, those feelings were intensifying.

Who do they think they are?!

The image flashed through his mind - of Mikasa, straddling Rivaille's lap, her legs wrapped around him as she moved against him. She had been topless, just pale smooth skin under the straps of her 3DMG.

Eren had caught a glimpse of her bare chest, the way Rivaille's tongue had flicked against her skin, the way those fingers had trailed teasingly across Mikasa's bare back, taunting Eren.

Rivaille had been shirtless as well, all lean muscle like Mikasa, but buffer, with broader shoulders. His arms must have been unimaginably strong from all that Titan slaying, from the look of his biceps and the way they had flexed when he held Mikasa.

Eren hadn't paid it much thought then, he had been too furious. But now, as he sat in his room, not doing much of anything, he couldn't forget the way Mikasa's fingers had fisted Rivaille's hair, or the way Rivaille's hands had held her waist possessively.

It bought up a flare of anger within him, and he wished that he could forget it entirely.

But there was another part of him that couldn't forget, that didn't want to forget.

What the hell is wrong with me?!

Eren shook his head, clearing his thoughts. But a moment later, his door swung open.

"What do you want?!" Eren growled, as Rivaille sauntered in.

"Your room is filthy. Do you ever wash it?" was the man's response.

"Why are you even down here. Shouldn't you be training with Mikasa?"

"Jealousy doesn't suit you, Eren," Rivaille remarked lightly.

"What the hell do you mean?!"

"Use your stupid little head. You'll figure it out."

"I'm not interested in your fucked up games!"

"Maybe you're not," Rivaille sat down on Eren's bed, reclining against the wall as he crossed his legs.

He was sitting there, so casually - as if Eren wasn't aware of what he had been doing with Mikasa for the past two months - it infuriated Eren.

"If you have no reason to be down here, could you please get the fuck out?"

"Careful, Eren," Rivaille warned. "Unless you want me to clean that shitty little mouth for you."

"Huh-"

Rivaille smirked. "Oh, I have my ways."

"I don't even know what you're saying. Get out."

"You know," Rivaille said after a moment. "If you wanted it that much, you could have just asked Mikasa. I wouldn't have given two shits."

"What are you even talking about?"

"It may have been a little awkward at first, since you're nowhere near as experienced as I am... but I'm sure even you'd figure it out soon enough."

Eren's mouth went dry as the meaning of Rivaille's words dawned upon him, and he was unable to believe his ears.

"What - I don't - want - that - " he sputtered, his cheeks reddening.

"Give it up, Eren." Rivaille rolled his eyes. "Mikasa may fall for your tantrums, but I can see right through them. You're jealous."

"I'm not jealous of you!" Eren spat, his eyes blazing. "That's the most retarded thing I've heard!"

And then suddenly, Rivaille had grabbed him by the shirt and yanked him down, till their faces were inches apart.

"Is that so? Then maybe you're jealous of Mikasa? Hm?"

His voice was low, velvety smooth - and Eren felt a shiver go down his spine. He could feel the Corporal's warm breath ghosting against his skin.

"Hei - chou -" Eren bit out, unable to say anything else.

Rivaille smirked then, a single finger trailing across Eren's collarbone.

"That's what it is, isn't it? You want some too, don't you, Eren? Dirty, horny little shit."

His words were biting, condescending - but Eren's skin felt like fire under his touch - and he could smell the Corporal's scent, feel Rivaille's bangs brushing his forehead.

Eren couldn't help but lean forwards, just a tiny bit. He would never admit it, but he found himself craving more of the man's touch. Rivaille's smugness and self-assurance was aggravating, but at that moment -

Is this how Mikasa felt, when -

The Corporal's knee brushed against Eren's leg, and he felt himself harden involuntarily.

Shit! This can't be happening!

But Rivaille only shoved Eren away, before standing up suddenly, in one fluid moment. His cold gaze swept over Eren's form.

Eren gulped, as Rivaille narrowed his eyes.

"You sick fuck. I barely touched you and you're already getting off on it? What would Mikasa say?"

And then he left the room without another word, leaving Eren with a bright red face and a throbbing erection.

That night, Eren dreamed of Rivaille and Mikasa. He didn't know if it was a dream as much as it was a nightmare.

He dreamed of Rivaille shoving her back onto his desk, working his lips over her body. He dreamed of Mikasa arching her back under Rivaille's touch, her normally calm and controlled countenance flushed.

"Heichou," Mikasa gasped, her voice trembling. "Rivaille-heichou!"

Rivaille thrust against her, pressing her to him. Mikasa's dark eyes were filled with lust, her lips glistening, her black hair fanned out below her.

"Please," she begged. "Please - "

He thrust into her again, but this time when she cried out, it was a different name on her lips.

"Eren! Oh - Eren - "

And then it was him on top of her, holding her, thrusting into her. Mikasa's nails scraped against his bare back.

"Eren, please - "

Eren leaned down to kiss her, but then suddenly, Mikasa was gone, her wide eyes replaced by smoldering icy blue ones.

"You!" Eren jerked his head back, horrified.

Rivaille smirked, flipping him over.

"You little shit. Stop denying it. You want me to fuck you, don't you? Just like I fucked Mikasa."

"What the - " Eren groaned, sitting up in his bed. He stared down at his hand in horror, and his now sticky sheets.

What did I just -

And then the Titan shifter bought his knees to his chest, banging his head against them.

"Fuck my life."

Author's Notes: Yup. Okay. I have no words for myself. There will be MikaEren in the next chapter. Since that's the only pairing here that has gotten no 'action' as such, just a lot of fighting/angst/verbal development. Along with RivaErenMika (finally!) if all goes as planned.

Please review!

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