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Armin sat up in bed, patting his high-waisted skirt to flatten it out as he drew his knees close beside him.

The soft pink glow of fairy lights decorating the bare white dorm walls cast a gentle light over his made-up face. Random anime music hummed quietly from the small, cheap speaker on his desk.

He kept tilting his phone, trying to find the right angle. From above… no, too MySpace. Front view? It made his waist look thicker than he liked, and it didn't show off the way his black thigh-highs dug faintly into the soft skin of his thin thighs.

A heavy slipped past his glossy lips as he shifted position, snapping another picture. Then another. Still, none of them managed to satisfy him.

Sure, Eren wasn't picky, but that didn't mean Armin was fine with sending something sloppy—especially if he didn't look his absolute best. If the sight of him didn't drive Eren absolutely crazy, he might as well not bother at all.

He dropped his phone onto the sheets and slid off the bed. The hem of his skirt brushed his thighs as he hit the scratchy carpet with a muted thud. A mirror selfie might work—but it would hide the face he'd spent thirty minutes perfecting.

Frustrated, he slowly pushed himself to his feet and padded around the small room until his gaze fell on his desk—littered with several cans of Monster, some empty, some still unopened.

An idea sparked in his mind, the corner of his mouth twitching as his fingers closed around a full white can—already picturing Eren's reaction.

Armin returned to the bed and plopped down, bouncing slightly on the soft mattress. He pulled his knees up again, tucking them close, then tugged at the skirt until it splayed out across his thighs—making sure the bows at the edge of his thigh-highs weren't obscured. He adjusted his top, tucking it in tighter, and propped his chest up before positioning the can upright against his crotch—fingers wrapping firmly around the bottom.

Perfect.

When he took the photo, he angled the phone so the lower half of his face stayed in frame, showing off the teasing grin curling his lips.

With a few quick taps, he dropped it into the message thread, thumbs flying as he typed out a caption.

"Want a sip?"

He hit send.

Eren didn't reply—just left him on read. Bastard.

A loud hiss cut through the soft music still playing as Armin cracked the can open, tipping his head back for a long swig—exasperated at being ignored. The warm pink tint he'd applied to his lips left a perfect print on the aluminium.

So he decided to sent another photo. This time, he held the can beside his face—tongue pressed flat and lewd against the tab—angling himself so both the lip stain and his made-up eyes made it into the shot.

Not long after, his phone buzzed.

"dude im in fucking class"

It wasn't the reaction he hoped for. Still, better than being ignored. He felt pleased enough.

Now he just had to wait for Eren's lecture to end.

With a sigh, his thumb flicked over the phone screen, scrolling through the album where he kept some of his more explicit photos of Eren. Shirtless gym selfies, mostly—Eren flexing in the mirror, showing off his well-developed physique—glistening with sweat under the harsh gym lighting.

And that stupid, signature smirk on his face.

But then there were the others. The naked ones. Eren sprawled across his bed, cock half-hard against his thigh and highlighted by the pink hue of his string lights.

Goddammit.

Flipping through the photos only made him more hot and bothered than before. But he refused to touch himself—not when the possibility of Eren ravaging him was on the table.

Once the hour finally passed, the door to Armin's dorm flung open with more force than necessary.

Judging by the timing, Eren must have bolted the second the professor dismissed them; the lecture had merely ended five minutes earlier.

"You teasing little shit."

Armin barely had time to react before Eren crossed the room in three long strides and scooped him up from the bed like he weighed nothing—phone slipping from his grip, as it dropped onto the bed. The next thing he knew, his back was pressed against the wall—Eren's knee slotted between his thighs, strong hands clamped tight all the way around his waist.

"Getting me all worked up while I'm out, huh?" Eren breathed, his voice a low, teasing murmur.

Flashing an innocent smile, Armin slipped into his sweetest voice—one hand Eren's shoulder the other twirling a strand of his chin-length hair. "I have no idea what you're talking about."

"You sent those pictures on purpose," Eren growled—sounding more worked up than angry. He leaned in close, mouth brushing the shell of Armin’s ear. The heat and roughness of his breath made Armin’s cock twitch with excitement beneath his skirt.

"But you weren't responding to me…" Armin pitched his voice into a soft whine, letting it falter at the end—biting his lower lip as he batted his lashes.

"Don't put on that pretty boy act with me."

Armin giggled. "But you like it."

Just as quickly as he'd been pinned to the wall, he was thrown onto the bed. The air rushed from his lungs as he bounced once—twice—against the mattress. Perfect. Exactly the reaction he'd been fishing for. Before he could gather himself, Eren was on him again, one hand pushing him down as he swung a leg over to straddle Armin's thighs.

From the corner of his eye, Armin saw Eren reach for his phone, which had apparently landed screen-up.

"Pervert," Eren teased. "Looking at those pictures, when I'm right here."

Armin rolled his eyes. "You're one to talk. I'm not the one who took them."

"Uh, yes you were?" Eren said, amusement threading through his voice as he pulled up the frilly skirt. "Lying little slut."

He gave Armin's ass a small squeeze. "Look at you. Not even wearing any panties."

"I'm saving you the trouble of taking them off." Armin turned his head over his shoulder to meet Eren's eyes, lips curved in a sweet, angelic smirk.

"I wanted to do it," Eren grumbled, pouting as he reached for the small bedside table. He rummaged through the drawer and came up with the bottle of lube.

When the first slick finger pushed inside, Armin let out an exaggerated moan—high-pitched, deliberately filthy. A second followed quickly, Eren working him open with a slow scissoring motion. Armin pressed into the touch, arching his back and lifting his hips higher.

A third finger, this time more slowly, stretched him out further. Eren was putting an awful lot of effort and attention into this prep. When a fourth one was inserted, Armin's nostrils flared, and he drew in a sharp breath through his nose.

"Are you gonna fist me or something?" Armin said, voice rough and impatient. "Hurry up."

“Are you sure you want me to do that?” Eren's voice curled with smug, twisted amusement. He leaned back, reaching towards the desk.

"Since you love these so much."

He chuckled darkly, holding up a Monster—original flavour—in front of Armin's face. He gave it a playful shake, the carbonated liquid sloshing softly inside.

"I was thinking you could use some proper preparation."

Oh no, he did not like where this was going. Sure, he'd taken Eren's cock and oversized dildos plenty of times before. But those were actually made with insertion in mind. On top of that, the object was rather girthy—even for Armin.

He would rather not have a carbonated enema. Still, when Eren had his mind set on something, there was no escaping it. Especially when he wasn't one to consider the possible outcomes.

"Don't worry," Eren said when Armin shot him a wide-eyed look. "It's nothing compared to my monster cock." A stupid smirk painted his face, smugness radiating of every word.

Armin snorted. "You wish."

The grip Eren had on his waist tightened, painfully so. He could already feel bruises blooming against his pale skin. Usually, Eren could be pretty gentle, but Armin knew what buttons to press to get his desired treatment. Despite the flowy skirt and rosy cheeks, he preferred it when he wasn't handled like a delicate little flower.

"Can't you use a sugar-free one instead?" Armin mumbled shyly, already accepting his fate. "I'd rather not get all sticky."

"Oh, picky, are we?" Eren mused. "How does Strawberry Dreams up your ass sound?"

"Fucking lovely," Armin scoffed sarcastically.

After fetching the desired flavour, Eren squeezed a generous amount of lube onto his fingers and coated the pink can thoroughly—rubbing it down with slow, lewd strokes, sliding all around—while holding it directly in front of Armin's face.

Armin tried not to roll his eyes.

A low chuckle slipped from Eren's lips as he pulled back. Then, without warning, he tapped the can against Armin's bare ass cheek with a wet smack.

Armin let out a small yelp before he could stop it—the slick metal unpleasantly cold against his skin. He forced himself not to tense for the insertion. Instead, he breathed out slowly, willing his body to relax, focusing on the music still drifting from the speaker.

The opening riff of The Rumbling by SiM filled the room. For fuck's sake.

Eren's humming along to the music didn't help, either.

"Gonna rumble that ass of yours," he said, poorly mimicking the melody.

A shudder rolled through Armin as Eren began easing the can inside. It didn't slide in smoothly—each push was slow, ragged, clumsy—caught between teasing and too rough.

Once Eren finally managed to force the thick canister past the rim, stretching Armin further than he was used to, it felt like he was being torn apart from the inside.

"I bet this breaks your current personal record."

Armin could hear the stupid smile in Eren's voice.

At a particularly rough thrust, his mouth fell open, a string of sharp gasps and a high, helpless yelp slipping free. He twisted his head, searching for a fistful of bedding to bite down on. Fabric filled his mouth—moans muffling around it.

Eren pushed it a little deeper. A loud groan tore from Armin's throat the moment the rounded end reached just far enough to nudge against his prostate, making his whole body jolt.

The lightly embossed surface warmed slowly inside him as he adjusted to the thickness. Every subtle movement of Eren's fingers around the base sent faint vibrations rippling through the thin aluminium.

"Fuck," Armin hissed between clenched teeth, eyes squeezing shut, fingers gripping the edge of the mattress tight.

"Heh, you size queen."

Suddenly, the feeling of being split open eased—just barely—and only then did he realize the can's walls had given in. Shit.

He tried to stay relaxed, to keep the aluminium from buckling any further—but his body refused to listen, clenching around it uncontrollably. The pressure had already cracked the top rim, the part Eren had inserted first.

Cool, carbonated liquid seeped out. At first it was only a slight tickle, then the aggressive, acidic sting of bubbles turned vicious against his tender insides.

A violent shiver jolted along his spine at the unpleasant sensation, and he instinctively arched his back. His breath snagged high in his throat, eyes blowing wide like someone had dumped a bucket of ice water over his head.

He let out a thin, helpless whine against the damp fabric stuffed in his mouth.

Whether the sudden rush came from the caffeine flooding his system, or simply from the cold prickle assaulting every sensitive inch—he couldn't tell. For half a second, the fizzy tingle was almost pleasurable—interesting, even—but the enjoyment was quickly swatted away by a slow, festering feeling.

The longer the drink pooled inside him, the more the obscene bubbling gave way to a fierce, burning ache. The acidity was far too harsh for that fragile area and unlike anything he'd ever experienced.

No—he definitely didn't like this. A shrill cry tore from his throat as he bit down harder on the soft fabric bunched between his teeth.

"Shit, you okay?" Eren asked, all playfulness gone from his voice when he registered the distress.

Armin answered with another muffled shriek.

Eren pulled the deformed can out quickly—but not fast enough to stop the pink liquid from spilling everywhere: across the frilly skirt, dripping in wet trails down back of Armin's thighs, soaking the thigh-highs through, and seeping into the mattress.

"Oops."

Like hell it was merely an oops.

A pained, pathetic whimper slipped from Armin as Eren gave a harder tug. The can had crumpled inward—misshapen, save for the rigid brim, which nearly caught on the rim of his hole on the way out. When it finally came free and the trapped liquid had somewhere to go, the raw, scratching burn dissipated slightly, but the irritation lingered.

"It's getting all over that pretty little skirt of yours," Eren said cheekily, delivering a few firm pats to Armin's ass—the callouses of Eren's palm scratching over his skin. The sudden movement made him flinch, the sting flaring brighter—followed by a subtle twitch he couldn't suppress.

"You good?" Eren asked, the smug edge gone from his tone.

"Fucking dandy," Armin gasped.

With a loud clang and a light chuckle, Eren set the dented can on the nightstand. Then he reached down and adjusted Armin's socks where they had slid down during all the squirming. He gave a small securing squeeze with one hand, thumb digging into the pale skin.

Then Armin felt it—a warm, wet pressure dragging along the back of his thigh, all the way to the curve of his ass—accompanied by a low, vibrating moan and a soft puff of hot breath against his skin.

Did Eren just lick him clean?

Eren fell back onto the mattress, knees first, the bed creaking under his weight. He shifted, unbuckling his belt in one swift motion and letting his jeans slide down. A quick shuffle of his legs, and the denim was off entirely.

Eren leaned in close, lips brushing Armin's ear. "Now for the actual monster," he murmured—low and sensual, all earlier concern stripped from a voice that sounded far too serious.

“Would it kill you to come up with some new jokes?” Armin asked quietly, fighting back a snicker at the lame attempt at seduction.

"What? You don't think I'm charming?" Eren replied, voice thick with feigned offence.

Armin barely mustered a raspy whisper. "No, and you have a high bar to clear now."

Eren barked a laugh, the sound dripping with amusement. "So you did like those bubbles, huh?" His fingers traced slow, lazy circles over Armin's hip. "What flavour do you wanna try next time?"

Peeved, Armin only huffed—refusing to dignify Eren with a single word.

Eren reached over to the nightstand again and grabbed the lube. He didn't waste any time— slicking himself with a generous amount before lining up against Armin.

The blunt pressure of Eren's cock against the sore, inflamed area wasn't exactly pleasant—but the cool slide of lube soothed the lingering fiery sensation just enough to take the edge off. Armin could only grunt as pain and pleasure crashed together, overwhelming him—Eren thrusting hard and deep, with no pretence of being careful anymore.

The one time he would've preferred gentleness—and now Eren suddenly had it in him to be a selfish bastard.

"Got any words left for me, pretty boy?" Eren's voice was rough, his hips rolling in deep, punishing strokes.

Armin didn't have it in him to speak anymore. All he could manage was a broken, needy sound too overstimulated by the clash of contrasting sensations. 

"Fuck, those pretty noises of yours are gonna be the end of me." He panted.

At least Eren was always quick to finish. He came with a low groan, and Armin followed soon after. Heat settled low in his stomach, spreading far and wide until his limbs went numb and the prickling ache in his ass faded, if only for a moment.

Eren collapsed beside him, chest heaving, his bun long since undone. Long dark hair clung to his damp forehead and the curve of his neck.

"Bet you broke a personal record too, with how quickly you came," Armin whispered between pants. "Better stop skipping cardio."

"You're lucky you're so pretty," Eren muttered, firmly grasping Armin by his cheeks, squeezing hard enough to force his lips apart.

"Not luck, just pure hard work," Armin rasped between his fingers.

"Too bad your fuckass bob got all fucked up then," Eren said breathlessly, removing his hand so he could ruffle Armin’s hair instead.

"Hey!” An exaggerated pout tugged at Armin’s lip. "I’ve been growing it because you wanted me to." He jabbed a finger between Eren's sweat-slicked pecks—earning a small, rough groan in response.

"Your face is a mess too," Eren shot back, grinning.

A low hum of faux displeasure rumbled in Armin's throat as he rubbed his cheek against Eren's shoulder—making sure to smear what was left of his makeup across his skin.

"Cute," Eren murmured, pulling Armin into his arms, their sweaty bodies pressing close.

Armin only pouted harder. Slowly, he broke the hug and forced himself upright on the bed. A sharp wince pulled at his mouth as the burning pain inside his ass flared up again. He inhaled sharply through gritted teeth, bracing his weight on his palms, fingers digging into the mattress.

With an exaggerated groan, Eren rolled off the bed and snatched the abused can from the nightstand.

Armin's eyes widened when he realized what Eren intended to do.

"Dude, that's so gross."

"What? I ate your ass the other day," Eren said with a shrug. He brought the can to his mouth, not breaking eye contact for even a second. When he finally lowered it, he let out a deep, satisfied sigh. "It'd be a shame to let it go to waste."

Armin shuddered, nose wrinkling in disgust. The lingering sensation of caffeinated carbonation fizzing inside him was more than enough to put him off energy drinks for a while.