This is admittedly not super well proofread but I just needed to make sure I got something out for Shiro's birthday, so I made this. Enjoy!

***

Sleep. That was the only thing on Shiro's mind as he strode down the castle hall, eyelids already weighing down. Allura had already pointed out the bags beneath his eyes during the meeting, but fatigue wasn't an excuse for him to skip out on diplomacy talks. Part of him suspected she had purposely ended the meeting early for him, but he would have to ask later.

The door to his room couldn't open fast enough. As soon as he was inside the dark room, his shirt was off and on the floor, allowing him to stretch his aching muscles. Not that he'd been using them a lot today, but they did occasionally ache with stress. He pressed down against his shoulder blades, sighing and even letting out a small moan—and then he saw it.

A familiar figure lay draped on his bed, legs stretched out on their side, body curving at the hip...

"...Keith?" Shiro rubbed his eyes and backed up to turn the light on, revealing Keith in his full Blade uniform..with a rose in his mouth.

"Hey, Shiro."

He was stuck between throwing himself at Keith and staying frozen where he was; instead, he reached for the rose to accept it from Keith's mouth, eyes traveling down Keith's body.

"You're back from your mission?"

"I'm right here, aren't I?"

He wasn't changing the position he was laying in—Shiro could already feel that becoming a problem against his boxers.

"Yes, but...what are you doing here? I mean, when did you get back? Did everything go well?" His heart momentarily stopped beating as he dropped to his knees and grasped Keith's hands. "Are you alright?!"

The smile that broke out over Keith's face was a wave of comfort over Shiro's stiffening bones—receiving a kiss to the forehead was the cherry on top.

"Yes, I'm alright, because I get to see you. I just arrived a little earlier. Were you heading to bed?"

"No!" Shiro looked down at his bare chest which said otherwise. "Well, I was, but not anymore."

"You can still head to bed, even if I'm here." Keith patted the spot behind him. "That's why I rushed back, after all."

Heat crept up Shiro's face as he glanced from the rose to Keith rubbing the bed right behind his ass. "You're being pretty straightforward today, aren't you?" He climbed over Keith and took his spot behind him, lying down to wrap his arms around him.

"Is it that obvious?" Keith sunk against Shiro's naked body, hands reaching up to hold his arm as it came around his chest. "Maybe I shouldn't have asked Lance for advice..."

"Lance?" Shiro sat up again immediately, observing the rose in his hand. "You asked Lance for help to talk to me?"

"No! Well, okay, yes, but it's because it's a special occasion!"

"'Special occasion'?"

"You've got to be kidding me." Keith sat up with something of a pout on his face, eyes digging into Shiro's as if attempting to force some sort of memory into his brain. When nothing happened, he just sighed exasperatedly and threw himself into Shiro's chest once more. "Happy birthday. At least one of us remembers."

Shiro's eyes widened, glancing at the rose once more before his hands instinctively came around Keith's shoulders. "My birthday...is it really the 29th?"

Keith's lips pursed together as he looked up thoughtfully. "Not quite, but it's the day after the 28th, so it's the same thing, isn't it?"

"I thought you didn't keep an Earth calendar? Wasn't that Lance's thing?"

He reached for Shiro's hand, guiding it to his face with a breath of relief. "For you, I'll remember what day it is. This is an incredibly important day to me, too, you know." Their fingers linked together. Their eyes did, too. "The day you were born was the day my life was guaranteed to be filled with happiness."

"Keith..." Shiro's lips quickly found Keith's as he gently set him beneath him on the bed, hands squeezing his back.

Keith's legs wrapped around Shiro's waist until he was clinging to him like a koala, mouth opening wider by the second. Pretty soon, kisses of intimacy and passion had become an intense make out session, with Keith bucking his hips up into Shiro's.

"I came here for you, Shiro," he gasped out, head leaning back, saliva dripping down his terribly messy chin. "Please, I want you!"

"I want you, too, baby." Shiro peppered kisses down his neck before pulling back to admire the scene of Keith sprawled out beneath him, face turned to the side with messy liquid all over it, be it sweat or their shared saliva.

As he fiddled with his belt, his eyes locked onto the bump of Keith's ass in his suit. "Did you wear that thing on purpose? Or did you forget to undress while waiting?"

Keith's fingers trailed up the side of his suit. "This? Lance suggested I keep it on. He said you'd enjoy the welcoming sight. He also suggested the rose...I thought it was just stupid, so you don't have to keep it. Blame him, he wanted me to go way overboard with stuff when all I asked was, 'how do I surprise Shiro for his birthday'..."

Shiro would have to give Lance his thanks at a later date as he slid his pants off. "Just seeing you is the perfect surprise. And the suit always looks perfect on you...why don't we get it off now, though?" His fingers were already beginning to lift away the chestplate as Keith chuckled.

"Aren't I usually the one impatient to have sex?"

His face flushed again, but Keith was already pulling his Blade suit off, shoulders bunching up dramatically as the clothing fell over his arms as if to seduce Shiro even further.

"I'm glad you're happy to see me." Keith reached forward to gently stroke Shiro's massive hard on through his black boxers, crouching down so his face was near the tent. "You always smell so good..."

"Keith..." Shiro's veins flared with heat as his balls were groped through the boxers.

"You're so hard and heavy right now...you must be real stressed out." Keith got up on his knees to wrap his arms around Shiro's shoulders, suit hanging around his waist. "You shouldn't be stressed out on your birthday."

"Then hurry and get naked..."

Keith smirked, pressing a quick kiss to the bottom of his chin. "Yes, sir."

Shiro took up the job of palming himself through his boxers, sitting back with his legs spread to watch Keith pull the suit down his hips. "You're extra sexy today."

"Yeah?"

"Maybe it's just because I haven't seen you in a while. I want to fuck you into the ground."

Keith dropped to all fours on the bed, completely naked now. "And you said I was being straightforward?"

"Shhh. Come here, baby." Shiro patted the spot in between his legs, which Keith quickly filled, ass waggling behind him eagerly. As always, watching him gave Shiro as many butterflies to the heart as it did his dick.

Without waiting for orders, Keith wrapped his lips around the clothed head of Shiro's cock, sucking through the boxers. He could only assume the taste still went through, because Keith moaned and sucked harder with each passing second. Still, Shiro couldn't keep his eyes away from his arched back, following it down to the dip that was his ass. It had been far too long since he'd feasted eyes on Keith's naked body...

"Turn around."

Keith looked up with mis mouth still around Shiro's cock, so he had to repeat himself before Keith did as told. As soon as he had turned, Shiro grabbed a hold of his thighs and yanked them up to his shoulders, drinking in the delicious sight of Keith's ass, just inches from his face.

"Sh-shiro..." Keith yelped, gulping as Shiro pressed his nose against his ass cheek.

"Keep doing your thing...god I missed this..."

"Can I remove your boxers? I want the birthday boy's cock, nothing in between."

He bucked his hips upwards invitingly, and without another word, Keith was pulling his boxers over his cock while Shiro's tongue swiped across his entrance.

A low groan escaped his throat at the way Keith's hole physically pulsed, as if in recognition. The boy's body was like a nasty drug; one taste had Shiro immediately diving in for more. His tongue was digging into his hot walls, mouth suctioning onto the entrance to suck on it, relishing in the sounds he was drawing out from Keith. Sounds that made his spine shiver while simultaneously soothing the ache in his muscles

Meanwhile, Keith's tongue was licking in circles around his cock, travelling the length down, showing every inch of it the appreciation it was meant to be given.

It was difficult for them to focus on their own pleasure while their tongues were busy with each other's bodies, and yet, at the same time, it was impossible to ignore what the other was doing. Like a constant game of tug-and-war, each of them would stop at random times to moan and grunt out the other's name.

Shiro's tongue dug in particularly deeply into Keith's walls, drawing out the highest of yelps from him.

"Shiro, that's...ah!"

Fuck. His prostate. Shiro's heart was immediately pumping ten times harder than before as his tongue darted forward again, chest swelling with more and more power each time Keith cried out his name and rolled his hips back against Shiro's face.

"Oh fuck...Shiro...it's been so...!"

"So long, I know baby." His tongue swiped over his lips as he admired the sight of Keith's wet hole beginning to stretch open, quivering each time his hot breath pressed up against it. "I guess separation really does make for hotter sex."

"I don't like being separated..." Keith looked back at Shiro, hands wrapped around the base of his cock as some form of penance for the momentary loss of his mouth.

Shiro reached forward to stroke Keith's face. "I know, baby. Me neither. But let's focus on us right now, okay?"

Keith beamed at him, upturned lips shedding sunlight down on Shiro. "Yeah. Keep eating me like that, babe."

"Can do." Shiro's mouth latched back onto his hole with fish-like puckered lips, sucking and coating him in even more spit as Keith's mouth went down on his cock.

"Oh fuck!" Shiro pulled back to lean his head against the wall, pupils expanding to take in the beauty of Keith bent over his dick, eyes shut as he took it down his throat with both hands wrapped around the base, twisting it like a screw to please the inches that he couldn't yet swallow. As he did so, his pinkies dug down into Shiro's balls ever so slightly—almost teasingly.

"Keith...move for me, baby. Move. Yeah..." He groaned and filled his palms with Keith's ass as his head bobbed up and down Shiro's cock, deep throating him until his face reached his hands.

His eyes were shut, as if hyper-focused, and he suddenly wasn't reacting to Shiro's breath on his hole as he released his hands from their hold on Shiro's base. Then, with Shiro watching with wide eyes, his mouth moved deeper down Shiro's length.

"K-Keith, you...oh...! Keith...suck my cock..." Shiro reached over his back to run his hands through Keith's hair, massaging his scalp briefly before grabbing his hair.

That had both of them moaning as Keith deepthroated the entire cock, nose pressed into Shiro's balls as he formed fists in his hair, eyes never leaving Keith's face.

"That's good...you're so good for me..."

Keith pulled up to look back at Shiro with even more saliva coating his chin now. His hands wrapped around Shiro's cock, as if to pump the wetness along the length even more. "Fuck me..."

"Get down then, baby. Let me up, let me fuck you."

He clambered off of Shiro, chest pressing down into the mattress to push his rump out for Shiro, who grabbed a hold of his waist.

"Is it just me, or did you get a lot better at sucking cock? Don't tell me you've been doing some practice. Sucking the Blades behind my back?"

Keith's face flushed red, still looking over his shoulder at Shiro. "N-no...I would never, Shiro..."

"I know, baby, I know," he assured, rubbing Keith's backside while the wet, swollen head of his cock grinded against his eager entrance. "Besides, it wouldn't matter. I'll fuck you so hard you won't be able to feel any other cock but mine."

"I already can't feel any other cock but yours."

Shiro grinned and leaned over Keith's back, abs pressing down on him as their lips met briefly. "I love you."

"I love you, too. Now fuck me. I've been waiting...waiting for this day."

"You can stop by and ask me to fuck you any day."

"I know..." Keith rested their foreheads together. "But this is special...right?"

Shiro observed his dark-grey eyes, shimmering with an almost violet hue in the lighting. Only Keith could make Shiro's cock this hard while also tinting his cheeks red at the same time.

"Of course. Are you ready?"

"Didn't you say you were going to fuck me until I can't feel any other—ah!"

Shiro growled, cock ramming into Keith. "If you're gonna be cheeky about it, then fine, I'll just fuck you."

Sweat was suddenly running down Keith's back as his head fell into the mattress. "Not...complaining..."

He couldn't help but grin at that, pressing kisses all along the back of Keith's neck. His cock was left buried eight inches deep inside of him, large balls hanging low until they were pressing against the back of Keith's balls, promising a hefty filling.

"You doing okay, baby? Didn't forget how big my cock is, did you?"

Keith's chest was heaving from beneath Shiro. Each breath sounded like it caused physical pain; Shiro ran his hands down his sides reassuringly. Only after several seconds of adjustment did Keith find his voice.

"N-no...I'd never forget...it's just been so long..."

"That's no good." Shiro grinded his hips forward before slowly pulling back, eyes falling shut as Keith's walls spread around his moving cock. "You used to be able to take me so much better. Guess I'll fuck your ass back open."

"Do it." Keith glanced over his shoulder, chest moving regularly again. That didn't last long, though, as Shiro rammed his cock forward.

Their shouts mingled together the way they had so many times before as Shiro's arms wrapped around Keith's torso.

Slow and steady didn't exist for them—it never had. The first few thrusts were experimental, but within the first ten seconds, Shiro's biceps were rippling as his teeth clenched together and he fucked his cock into Keith.

The sound of his balls slapping Keith's balls matched each of the boy's screams.

"Louder," Shiro breathed into Keith's ear, hand roaming up to hold his throat from behind while his other hand found its grip in Keith's hair. "I wanna hear you get louder for me, babe."

Keith was tearing the bed sheet off of the mattress, pausing to catch his breath. Naturally, Shiro couldn't allow that as his cock hammered forward once again, spurred on by the feeling of his hot walls closing in around his cock. It was familiar yet not at the same time to the point where it was almost worth not getting to fuck Keith for an extended period of time just for this moment. Almost.

A lack of air should've left Keith scrambling to find his voice, but it instead just left him screaming even louder, slave to Shiro's commands as he dropped his hand from Keith's throat to slap his ass lightly.

"You're as tight down here as I remember. Glad all my fucking didn't have any long-lasting effects on stretching you out too much."

Keith's screams turned to whimpers as his hair was yanked back harder until he was practically looking at Shiro upside down, back forced into an arch even though it was arching anyways in response to Shiro's dick.

"Shiro...I missed you...missed your cock in me..."

"Missed you too...fuck! I've been missing this so much...I've got all this stress, and I've got nothing to do with it without you around, babe...!" He grunted, hip bones grinding into Keith's ass as his cock reinstated its shape into Keith's ass.

Keith opened his mouth to speak, but instead slammed his head into the mattress once more, freeing his hair from Shiro's hold while violently fucking himself back on Shiro's cock. "Shiro! I...keep doing that...my cock..."

Both their eyes fell to Keith's cock as Shiro fucked him, balls slapping against Keith's until his entire cock was swinging with each thrust.

Shiro grinned. "Are you getting off on feeling my balls against yours? You wanna cum just from that?"

"It's your cock, too..."

"Of course, but tell me." He leaned across Keith's back to breathe into his ear again, tongue flicking out as an extra reward for Keith's shudders. "Do you want to cum from feeling me fuck you? Do you want my balls to push the seed out of yours?"

"Yes!" Keith gasped, eyes wide as if the answer were obvious. "God yes, Shiro, fuck me, make me...! Please!"

He rose onto his haunches once more, fucking Keith with a vengeance. Keith's balls slapped back against his as the smaller boy desperately pushed back against his cock, bed sheets completely torn up from the mattress. Then, he was cumming.

The option to pump Keith's cock through its first climax was tempting, but Shiro refrained and kept thrusting to help him ride his orgasm off instead.

Constant chants of Shiro's name left Keith, only to turn into screams all over again as Shiro rammed into his prostate.

The cum that had already been leaving Keith's cock fountained out even more, and once it was over, Keith crawled off of Shiro's cock and got down on his back, hands spreading his hole.

"Hurry...hurry...please!"

A lust akin to an animal hunting its prey glinted in Shiro's eyes as he immediately rose above Keith once more, filling his gaping hole with his cock.

Keith writhed beneath him, body vibrating its pleasure back against Shiro as they fucked while staring at each other.

As soon as Keith's legs wrapped around Shiro's waist, his eyes dilated, and he lost all sense of speech.

Sex. Cock. Fuck. Those were the only things that mattered in that moment as his balls slapped Keith's ass now, as if representing Shiro's words while Keith arched his back and screamed to the heavens; he mostly just screamed Shiro's name.

Somehow, fucking Keith like this turned into sitting back and fucking up into Keith as he sat on Shiro's cock, arms and legs still wrapped around his body while they fucked upright on the bed.

"Shiro...Shiro, kiss me...kiss me, please..."

Their lips smashed together messily, and yet, it was still the most put together either of them had felt in what seemed to be forever to them.

Shiro squeezed Keith's ass cheeks together, as if creating as small an entrance as possible for his cock as he set out on his mission to completely ruin Keith's body.

More chants of Shiro rose up before Keith threw his face against Shiro's neck, crying out as the larger man fucked him through his second orgasm. Not even once did he pause to let Keith process the pleasure.

With each thrust upwards, Keith grinded his hips down against Shiro's balls, riding him and stringing him along despite his finishes.

Their lips found each other again and again as Shiro's hands roamed down his back. He needed every inch of Keith, every semblance of physical stimulation he could get until everything was just Keith.

"You getting close yet, big guy? I can feel it."

Shiro groaned, eyes squeezed shut. It was Keith's turn now to have his hot breath in Shiro's ear, face pressed into his neck as he continued hugging him like a koala while riding his cock.

"How long has it been since you masturbated? Since you came?"

He couldn't even imagine the last time he'd came. Keith didn't even need him to say it as he gasped and grinded his hips down harder.

"You gonna finally cum now? Let it all loose? I can feel the way your cock is gearing up to shoot a huge one. Give me it, Shiro. I need it. I've been craving it..."

"Fuck!" Shiro's eyes flew wide open as he slammed Keith down on his cock like an animal in a rut, and before Keith's back could even give up on supporting him completely, he was holding him against his chest and filling his insides with his thick cum.

His balls dumped everything they had as Keith's walls squeezed around him, reflecting Keith's desperation as he moaned and held onto Shiro tighter, rocking back and forth on his cock just slightly.

Shiro bucked his hips up with every other shot, grunting and biting down into Keith's shoulder. Once he was done releasing his pent up sperm, he collapsed them both onto his bed. Blankets were forgotten. They were both a sweaty mess, anyways. Yet, they wouldn't have it any other way.

"I don't want to ever forget what it's like fucking you," Shiro breathed out, slowly blinking his way out of his sex high as Keith snuggled against him.

"You'd better not ever forget."

"Then maybe you should be waiting in my room for me more often."

Red crept up Keith's face as he avoided looking Shiro in the eyes. "...you know I can't. The Marmora—"

"I know." Shiro pressed his lips to Keith's forehead and held them there so Keith wouldn't feel obligated to look up at him. "I know. You have to do your thing. It's okay. My love for you will never grow weaker. Nor will my love for fucking you."

Keith grew still in Shiro's arms, and after a minute of silence, he let his eyes fall shut and buried his nose in Keith's hair...only for him to finally speak up again.

"Hey...I'm sorry. I know I'm the reason you haven't been getting much sleep lately."

"What?" Shiro pulled them away a bit to observe Keith. "That isn't—!"

Keith rose his eyebrow, successfully stuffing a sock in Shiro's mouth.

"...it isn't you. It isn't your fault. It's just...hard to fall asleep without you, sometimes. Especially without getting to talk to you or see you first..."

"Me too, babe, I promise." Keith snuggled close to him again. "I'm back from that mission, though, so I should be able to talk to you every night again before bed...okay?" His fingers were kneading into Shiro's muscles wherever he could; of course he could feel his stress just like that.

Shiro sighed, kissing the top of his head. "Yeah...I'd like that."

Keith grinned up at him. "Happy birthday, love. I hope the rest of your day wasn't too stressful. You look tired."

He was tired. Still, he kept his eyes open so he could look at Keith and press their foreheads together. "It doesn't matter what the rest of the day was like...because you instantly made up for it."

Their lips touched.

"I love you."

Their lips touched again.

"I love you, too."

They fell asleep cuddled together on Shiro's bed, indulging in the warmth and comfort provided by each other's body and presence.

They didn't need a blanket. They were each other's blanket.

***

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