Work Text:
When asked what was the most beautiful thing they’d ever seen in their lives, most people would probably name a particularly vibrant sunset, or a thicket of their favorite flowers, maybe their pet on a particularly good day, their favorite food prepared to perfection, or perhaps even a neon-lit cityscape at night.
For Eijiro, it was Katsuki’s smile.
To see his boyfriend’s genuine, no-holds-barred smile was rare to an absurd degree, a shining gem in a mountain of smirks and grins of malice, flashes of teeth that some might consider a smile, but were meant as anything but. Sure, there were the soft little quirks of Katsuki’s lips in the yellow light of the morning as they roused, magnetized to each other’s warmth and tucked together seamlessly, coaxing gentle mannerisms out of the explosive blond, and there were times when Katsuki would win at some video game and cackle endlessly in a pouting Eijiro’s ear, grinning toothily and loudly boasting about his victory, but there was something about this smile, the one Katsuki wore when he didn’t think anyone was looking, that made Eijiro’s knees weak, that made his heart flutter so insistently he had to put a hand over it to keep it from bursting out of his chest, that reminded him, in an overwhelming rush of emotion, how much he loved Katsuki.
This was one of those moments, and Eijiro had been caught entirely unawares as he pushed open the door to his boyfriend’s room, a particularly mind-boggling extra credit assignment clutched in his hands he’d planned on asking for help with. He’d nearly opened his big mouth and ruined it on accident, but he supposed Katsuki might not have heard him even if he hadn’t stopped himself from blurting out the blond’s name.
Katsuki was standing with his back to the one window in his room, the heavy blackout curtains uncharacteristically pulled aside and knotted to allow the late afternoon sun in. There was a pair of stylized, expensive headphones nestled into his flurry of blond spikes, quietly pulsing a beat Eijiro couldn’t quite make out, and the black cord trailed down the column of his neck and into his t-shirt, emerging again at the hem to wrap around his hips and disappear into his back pocket. His eyes were all but closed, nothing but shining streaks of crimson between pale lashes, and he was happily bobbing and shaking his head to an inaudible beat.
It took a moment, since Eijiro’s brain simply stopped altogether at the sight of him, but his gaze eventually trailed down to where Katsuki’s mouth was moving, pink, kissable lips forming silent words. Lyrics, Eijiro thought belatedly.
Katsuki was singing.
Eijiro watched, enthralled, for a few precious seconds as Katsuki sang soundlessly until he ran out of lines to lip sync to and just smiled his perfect smile again. Eijiro’s eyes wandered down to where Katsuki’s broad shoulders were tensing and shifting under the thin fabric of his shirt, his calloused hands lifted to mimic a drum beat that was probably much more difficult than Katsuki was making it look. He was naturally rhythmic, a fact that assisted him in many facets of his life, and that paired with his incredible reflexes made him an alarmingly good musician whenever an instrument was shoved into his grip. Little drops of sugary sweat beaded on the slope of his forehead and the defined curve of his biceps, adding a glistening sheen to his unblemished skin.
He was stunning like this, silhouetted by liquid gold, the light filtering through his untamed hair like bubbling champagne, gleaming through the window panes to turn the patches of pale skin peeking through his ripped jeans aflame. Katsuki’s hips were shaking and moving to the beat, his stomach rolling to match, and his shirt pulled up to display a sliver of well-defined abs leading up from belted jeans. Eijiro was suddenly very flustered, a tingling warmth flooding into his chest and quickly rising to his cheeks, flushing them a shade of red he’d guess would accent his hair quite obnoxiously. His eyes darted back up to Katsuki’s face, feeling scandalized and embarrassed for reveling so much in what was clearly a private moment, only to find a shocked, blushing expression staring right back at him.
Eijiro squeaked. Like, a genuine, who-stepped-on-a-squeaky-toy-oh-shit-that-was-me, squeak.
Katsuki didn’t look very amused. He yanked his headphones off his head and rested them haphazardly around his neck, pulling his phone out of his pocket and pausing whatever song he’d been listening to before returning it. His scowl was genuine, but the hint of fondness in his eyes and the tinge of pink dusting his ears gave Eijiro some small hope that his boyfriend wasn’t too upset with him. It would be a shame if such an inviting scene was ruined by Eijiro’s surprise appearance and subsequent drooling.
“I, um, I came to ask you a question about the homework…” Eijiro explained, bashfully rubbing a hand against the back of his neck and smiling awkwardly, knowing that probably wouldn’t diffuse the blond’s attitude and underlying embarrassment at being caught.
Katsuki huffed, clicking his tongue and shifting his weight. “Should learn how to knock, Shitty Hair.”
Eijiro chuckled meekly, chewing gently on the inside of his cheek. “I did knock, Kats.”
The blond blinked slowly, and the redness spread from his ears to his cheeks, blooming bright against his pale skin. “Well- I- I didn’t hear you, obviously,” he groused, defensively crossing his arms over his chest. His lips puckered slightly in a pout he probably doesn’t even realize he was making, and god did it make Eijiro want to kiss him.
A flustered Katsuki, although much less rare than a smiling one, was a gift Eijiro always did his best to take in stride, usually by means of atrocious flirting that definitely wouldn’t work if Katsuki didn’t love him so much.
“Mmm?” Eijiro hummed in his throat, nudging closer to his boyfriend and shyly glancing up at him through his lashes. “And why’s that?”
Katsuki startled a little at the blatant teasing, staring down at him with wide eyes, and the bridge of his nose began to redden too. “Wha-”
Eijiro chuckled lowly, a little embarrassed with himself but glad it was having the effect he was aiming for, and reached forward to cup Katsuki’s cheeks in his hands. They were a touch warmer than usual, smooth and soft with near-invisible peach fuzz, chubby and delightfully squishable. Eijiro leaned in and Katsuki arched up slightly to meet him, drawn in by the closeness, and their lips met gently. Katsuki’s arms snaked around Eijiro’s waist, and Eijiro tilted the blond’s head to get a better angle, his homework long forgotten on a side table somewhere behind him.
Katsuki’s lips were perfectly soft, pliable but anything but complacent, and his hands roamed Eijiro’s back as they kissed, exploring the grooves of his skin like he had all the time in the world to just feel . They’d had a fair amount of kissing practice already, what with the fair share of hormones between them and Katsuki’s desire to excel at everything he tried. Eijiro had been nervous at first about all of his sharp edges, but they’d learned to navigate it, and if Eijiro was having a good day, he might admit that it seemed like his teeth in particular were attractive to Katsuki. Leave it to his overachiever of a boyfriend to enjoy the extra challenge of two rows of shark teeth.
The blond broke Eijiro out of his thoughts as he pulled away, gazing up at him with those pretty red eyes of his. Eijiro waited patiently, knowing that look to be the one Katsuki wore when he was puzzling out how to say what was on his mind, rolling his hands over Katsuki’s petite waist.
Katsuki licked his kissed-red lips and smiled softly. “Thanks… for tolerating me.”
Eijiro smiled and crooned, pecking kisses on his protesting boyfriend’s mouth and cheeks as his heart swelled in his chest. He wrapped Katsuki up in his arms and smothered him in a tight bear hug that made the blond wheeze lightly and squirm half-heartedly. In the beginning of their relationship, Eijiro might have missed the underlying meaning of those words, but now that he understood Katsuki’s code, he knew how much it meant. Katsuki was used to hiding himself behind a mask of intolerable arrogance and abrasiveness, but what that left him with at the end of the day was a deep pit of loneliness he had resigned himself to early on in his life. Eijiro was determined to change that, and the closer they got, the more Eijiro got to see little pieces of Katsuki the outside world wasn’t privy to.
That was Katsuki’s way of thanking Eijiro for letting him be himself with him.
“Aww, I love you, Katsuki!” Eijiro chirped, like a love-struck sap, “being with you makes me happier than I can even explain.”
“Shut up,” Katsuki growled, unable to fight the smile spreading across his face, “you mushy weirdo.”
Eijiro laughed loudly, releasing his boyfriend so they could look at each other. The amusement in his chest slowly simmered into adoration, and he cupped Katsuki’s cheek once more. “You have the most beautiful smile in the world, you know,” Eijiro murmured softly, eyes crinkling at the corners.
Katsuki screeched and wrestled himself out of Eijiro’s hold, his persistent blush now covering his whole face, and Eijiro’s blond gremlin of a boyfriend stomped away, embarrassed. Eijiro followed along, grinning widely as laughter shook his chest.
He’d never get tired of that smile.