Posted originally on the Archive_of_Our_Own at https://archiveofourown.org/ works/4645731. Rating: Explicit Archive Warning: Rape/Non-Con, Underage Category: M/M Fandom: Shingeki_no_Kyojin_|_Attack_on_Titan Character: Erwin_Smith, Armin_Arlert, Eren_Jaeger, Mikasa_Ackerman Additional Tags: Incest, Erwin_is_Armin's_father, Masturbation, I_REGRET_THIS_SO_MUCH, Why Did_I_Write_This? Series: Part 8 of AD's_Drabbles_and_Snkkink_Meme_Fills Stats: Published: 2015-08-24 Words: 2587 ****** At What Cost ****** by AlvaDomer Summary A father's duty is to protect his son. Notes I... Yeah... I don't really know how to describe this one. Be careful for sure, because this story contains rape and no one deserves to get triggered. I'm not sure why I wrote it. Saw it on snkkink, wrote it in under four hours, and haven't posted it for two weeks. And now I've been given the courage to post it, unbeta'd because I love my editor too much to subject them to this. That's how uncomfortable I am about this fic. Incest is probably the most twisted form of rape I'm willing to write. But just because it's from Erwin's perspective does not mean that I condone incest in any way. If anyone is interested in a second chapter just to see what happens to Armin at school, I'm willing to write it. I'm sorry if this offends anyone, I hope you all can forgive me. Here's the prompt. I had already posted the story there to gauge people's reaction to it. So here it is: http://snkkink.dreamwidth.org/19979.html?thread=10118923#cmt10118923             Erwin sunk his teeth into his lower lip, stifling a groan. He couldn't be caught, not now.             The shame washing over him in waves had to compete with the mind- numbing shocks of ecstasy coursing through his body with each stroke.             Of course he knew he shouldn't be doing this, he knew how fucking wrong this was; and yet here he was, hunched outside the bathroom with the door ajar, a hand in his pants pumping his cock furiously.             But when he saw his son like that, could anyone really blame him?             Armin was almost fifteen now, a man in most countries. It couldn't be that wrong, could it?! Plenty of people were married by his age! And with each bead of water sliding sensually down that smooth, ivory skin, it was nearly impossible to believe that his boy hadn't been taken already.             Watching him hum cheerfully, obliviously putting on a show for his old man, filled Erwin with disgust, horror, and a need he had never felt so deeply even for his own wife.             Erwin let his imagination run wild as soap suds sunk into places that he wanted to kiss and lick and suck completely dry.             Armin let out a small sigh as he ran his delicate fingers through blond hair soft as Irish string, and Erwin nearly came right then. He wasn't going to last much longer on these secret shower sessions alone.             Erwin had to have his little boy.             "Oops," Armin mumbled, bending for the dropped bar of soap. His perfectly round ass, firm and full from cross-country, was put on open display, and Erwin flushed with shame and pleasure as he flooded his boxers with cum.             As the high faded, the self-loathing only continued to grow. I'm going to Hell.                                                                                                      ...             Erwin couldn't help but feel guilty when he watched their faces fall—especially Armin's. He had never denied them before; Eren and Mikasa had slept over every night of Armin's birthday since the children were seven.             But this, this was for Armin. It's a wonder he hasn't been taken already. That thought had haunted him since the evening he'd had it, and the more he pondered it, the more Erwin realized it was true. He was lucky, the both of them were, that Armin had still maintained his innocence. With such pretty plump lips and a gorgeous ass, Erwin found himself counting his blessings that Armin's virginity hadn't been taken by force. That's why he had to deny Armin this sleepover; why he had put so much planning into this night. Yes, it was definitely for Armin's sake.             "Byyyyyye Armin," Eren droned, dragging his feet despite how he was herded toward the door. He shot Erwin a bitter glance, obviously forming a grudge.             Erwin just gave him a warm smile in return, resisting the urge to pick him up and throw him out. "You'll see the birthday boy tomorrow," he laughed, but Eren hardly looked sated.             "I know, but—" he started to whine, but Mikasa grabbed his arm, giving him her look.             "Mr. Smith said it's time to go," she stated flatly, deadpan as ever despite being...probably upset. Erwin had never quite gotten the hang of distinguishing that girl's emotions.             "Bye guys, thanks for coming!" Armin chirped, flashing his brightest, cutest smile, and Erwin was suddenly fighting to keep the blush from his cheeks.             Hugs all around, and they were finally alone. "Come on kiddo, I want to spend some time with my favorite son on his special day," Erwin sighed almost longingly, wrapping an arm around Armin's shoulders.             Armin just snorted. "That's such a dad thing to say. I'm your only son," he chided, some disappointment about his friends still reflected in his eyes. But he wasn't complaining, because Erwin's baby was just that selfless.             God, what am I doing...             "That's why you're my least favorite too," Erwin quipped instead, swallowing his shame and kissing the crown of Armin's head.             That beautiful laugh, bright and pure, went straight to Erwin's dick. He crossed an ankle over his knee subtly as they sat on the couch together, praying that Armin didn't notice.             After watching Repunzel and listening to his little genius pick out all the historical inaccuracies, Armin mumbled something about wanting to go to bed early. Erwin knew that translated to "I'm going to text Eren and Mikasa in bed until three in the morning" but he didn't mind.             He had plenty in mind of what they were going to do in bed instead. For Armin, he reminded himself anxiously.             Erwin waited for the clock to fade to eleven-thirty before he made his way up the stairs. It seemed Marie really wouldn't be home any time soon, just as promised, and that meant no interruptions.             Sure enough, when Erwin entered Armin's room softly, his boy was awake, tapping away on his phone. He glanced up and smiled sheepishly as Erwin approached, setting the device aside as he greeted, "Oh, hey Dad. I thought you went to sleep already."             There's no way I could, not when I have you to myself, Erwin thought before he could even help himself. But it was so painfully true. He would have probably been awake for endless tortured hours, thinking of nothing but the different ways he could fuck his baby into the mattress.             Armin was already flat on his back, smiling as if begging for his father's dick in his ass. There was no questioning it now, Erwin was doing this.             Sitting beside him, Erwin began stroking Armin's cheek as he murmured, "I'm sorry about your friends."             Armin only shrugged. "It's okay, I know you wanted to spend time with me too. We can always have a sleepover this weekend," he explained easily. Always so forgiving. Armin really was perfect in every way.             "I love you so much, you know that?" Erwin suddenly announced softly, tucking a lock of hair behind Armin's ear.             "Y-yeah, of course. Why are you telling me this all of a..." Armin's voice dropped off, eyes widening, deepening with concern—almost fear. Did he know? Could he really have figured it out already?! "You're not about to...you're not going to tell me that you and Mom are getting a divorce or something, are you?" he nearly whispered.             The air rushed from Erwin's lungs in a sigh of relief, even a slight laugh. "No, no! Not at all, Armin! I still love your mother very much," he assured him, leaning forward. "But I love you more."             "Wha—" Armin let out a startled squeal as his father's lips met his own. It was passionate, desperate, with Erwin's tongue snaking out only to meet Armin's teeth.             You monster! You fucking bastard! This is your child, your own flesh and blood! Erwin's mind screamed as he straddled Armin's hips, snatching his boy's jaw in one hand and a flailing wrist in the other.             He simply chose to ignore the wild terror in Armin's eyes, pretending that the beautiful blond wasn't put up such a pathetic fight.             When Erwin finally pulled back from the kiss, he managed to start, "Now Armin," but that was all. Armin instantly started trying to scream, and as much as it killed him inside to have to do it, Erwin clapped a hand over Armin's mouth. "Shh-shh-shh, it's okay, kiddo," he tried to soothe, this smile both pitying and pitiful.             In his fantasy world, Armin would give himself over all too willingly; eagerly rolling into any position his father asked, mewling and moaning like a cheap whore.             But this Armin, the real Armin, his lovely little boy, clawed at Erwin's arms and shrieked past his hand. "It'll be over before you know it, I promise," he tried again to calm the light of his life.             Armin only kicked harder, flailed more violently, when he saw the duct tape in Erwin's hand. This isn't right, he thought, pain clenching his chest as he slapped a strip over Armin's trembling lips. How could I do this? he wondered as he taped Armin's wrists behind a wooden headboard post.             Erwin gritted his teeth. For him. I'm protecting him, he reasoned as he unbuttoned Armin's pajama top. "I'm going to take good care of you, Armin," Erwin assured him, feeling his cock twitch against his thigh as he saw Armin's hairless chest. "I'll make sure your first time is the best you'll ever have."             With that, he dove down, dragging his tongue along a small pink nipple. Armin's entire body jolted and his kicking became even more frantic, muffled screams ringing throughout the room.             "It feels good, I promise," Erwin swore, lifting his head for only a moment. As his tongue swirled around one nipple, his hand found the other, circling and pinching until it was perky and begging to be sucked.             How many times had he dreamed of this moment; had he watched from afar only able to imagine what it would feel like to get a taste. His boy was just as sweet as Erwin imagined he would be, leaving a light trail of kisses from Armin's breastplate downward.             "Nnn! NNN! Dmd, nnn!" Armin screeched as loudly as the gag would allow, the first tears trickling down his face as Erwin pulled down his pants.             "My darling boy," Erwin whispered, rubbing a large hand over Armin's groin. The Spider-Man briefs came off next, and Erwin let out a gasp of admiration.             No amount of water or shower steam could compare to how lovely his boy was up close like this. With the pop of a cap, Erwin smothered his fingers in lube from the small tube in his pocket. "This is all for you," he cooed, taking Armin's limp dick in his hand.             Armin let out a horrid, choked sound, warped by fear and disbelief. He shook his head vigorously, pleading the only way he was able.             But Erwin simply repeated the gesture. "I have to do this, Armin...before someone else does," he tried his best to explain. Working Armin's shaft over expertly, Erwin continued, "Don't you understand? This is happening because I love you more than anything."             No matter how mature he may be to the rest of the world, Armin's body was still incredibly young. So Erwin wasn't surprised when his boy didn't last long, letting out a wail as cum splurted across his stomach.             "That's a good boy," Erwin praised, lapping up the white sticky fluid without hesitation. Armin was crying even harder now, even as Erwin took his member into his mouth to suck him clean.             Erwin still tried his best not to be offended. Armin just didn't understand yet how much this was helping him. He didn't know that in the end, this would all be okay.             With a fresh coat of lubricant, Erwin slowly sunk his index finger into Armin's asshole. His boy began squealing and squirming almost viciously, yanking against his bonds as he bucked his hips in panic.             Such blatant fear from his own son stung Erwin to the core, but such delicious tightness was something he'd never felt from anyone else. The way Armin fit around his finger like a vice, it was as if his baby had been born for this.             "It's alright Armin, I'm going to make sure it hurts as little as possible." Erwin cringed as Armin clenched even tighter in fear. "It's okay, it's okay," he repeated over and over, but a second finger did anything but calm his boy.             Scissoring the two despite how Armin writhed finally made him loosen, however slightly. Erwin managed to slide in a third, but with the way Armin was fighting, it was still going to hurt more than he had hoped.             "I'm going to be as gentle as I can, but this is going to hurt a bit," he admitted, unzipping his jeans.             "Dmd! DMD DNN! DNN, PLMM!" Armin shrieked as Erwin forced his boy's legs apart even further. He focused on guiding his throbbing cock toward Armin's entrance; not the terror or barely distinguishable cries of 'help me' or 'rape'.             Erwin definitely didn't hear 'Dad stop'.             But he did hear Armin's voice crack, watched his blue eyes roll into the back of his skull in agony, as Erwin began to plunge into him.             But it didn't matter how much it hurt his boy, it was still saving Armin in the end. Of course, it had to! So he only let out a guttural groan, eyelids fluttering as Armin's silky heat embraced his cock in near-sinful tightness.             Armin's face shined with snot and tears, his kicking becoming awkward and spastic. "Don't worry, Armin, you can take it," Erwin encouraged, taking almost the entirety of his boy's waist in his hands.             Erwin began pumping back and forth slowly, reassurances melting away into breathless curses. "Oh fuck," he moaned, trying not to hold Armin too hard. As much as he wanted to, he couldn't risk leaving bruises. Armin's first time needed to be loving, and gentle.             As he slid balls deep with each slow thrust, Erwin wished he didn't have to cover Armin's mouth. How he wanted to kiss those wonderful lips in a moment like this. He was almost certain he had been Armin's first for that too.             This was all for him.             Erwin wasn't even sure how long he lasted, admiring every slope of Armin's curvy little body as he grunted and groaned in pleasure. He couldn't believe it was possible, but Armin felt even better than he had dreamed.             He finally came with a low, "Armin," his boy's name on his tongue like a prayer.             Armin recoiled as much as his bindings would allow when he felt his father cum inside of him. He continued his pleas halfheartedly, but Erwin only wiped a tear from Armin's face, kissing his cheek.             "You were so wonderful for me," Erwin sighed, a tone he realized he had used with only one other person: his wife. He knew he loved his baby more. "You mean the world to me." Pulling out carefully, Armin still flinched, head turned away to sob into his shoulder. "Armin, Armin sweetheart, it's okay. You took it so well!"             Armin might as well have been deaf. The praise obviously washed right over him, ignored in favor of tears.             "Please don't cry, kiddo." The nickname only made Armin squeeze his legs together. "Let's talk about this, okay? There's no need to be so upset," Erwin insisted. "I'm going to take the tape off now, alright? If you start screaming I'm going to have to put it back on. Please don't make me do that to you."             Armin gave no sign of acknowledgment, but when Erwin pulled the tape away, his boy remained obediently silent.             "We can't tell anyone about this, not even Mom. This needs to stay our little secret," Erwin continued as he unbound Armin's wrists. Thankfully there were no marks left behind. "Understand?"             Armin nodded slowly, a faraway look in his eyes. He made no move to pull on his pants or even get cleaned up.             "Alright. Good," Erwin muttered awkwardly, throat constricting when Armin flinched as he tried to stroke his hair. "You might have a limp tomorrow," he admitted, continuing on with his one-sided conversation. "If anyone asks at school, just tell them you fell, alright?"             Armin nodded again, staring through the ceiling.             "I love you to the moon and back," Erwin whispered in Armin's ear, and gave him another long kiss on the lips that his boy didn't even try to fight against. "Happy birthday, Armin."   Please drop_by_the_archive_and_comment to let the author know if you enjoyed their work!