Karkat (hearts) Nepeta: marching band AU where the ferocious clarinet section leader has a crush on the puny tuba player
You'd met each other that first summer practice, freshman year. "Nepeta Leijon," you'd said, sticking out your hand and smiling gently at the lanky, almost panicked-looking guy. "Clarinet," you'd clarified, shaking the clarinet in your other hand gently, as if he'd not seen it. He sort of stared at you, all albino skin and sunscreen (so much you'd smelled like it all day, and you struggled to remember if you'd touched him because how else would it have gotten on you?), and then almost reluctantly reached out to return the handshake.
"Karkat…Vantas," he'd replied, and his voice had been so gruff and he'd frowned so sternly at you (but it wasn't off-putting, because his eyes said he was frightened out of his mind). And then grudgingly, as though an after-thought, "I play tuba." And you'd smiled broadly, pleased as punch to have made a new friend, even though the upperclassmen were screaming for people to get back into position. You ate lunch with him every day during summer band, and introduced him to the other eclectic bunch of friends you'd cobbled together over that first day.
And it just sort of grew like that. Terezi, the girl who like dragons as much as you liked cats, brought her foster sister and best friend Vriska (who brought her sometimes boyfriend, Tavros, with her), Equius, your best friend, tried to bring in Aradia (she didn't always stick around but she brought with her Sollux, who was quickly involved in a hostile sort of friendship with Karkat), and eventually there were twelve of you guys eating sandwiches and salads in the appropriated, empty orchestra hall.
Which was nice, even if Feferi was a junior, and her best friend Eridan was a stupidly haughty sophomore. Between her and Gamzee (a completely stoned percussionist, who also happened to be a second-year senior), you had the upperclassmen part of the group completely covered! And when summer band was over, you hardly expected to see most of the group outside of afterschool practice and football games!
So you were of course, completely and pleasantly surprised to find Karkat and Terezi in your band class period. And, over the course of the school year you found yourself completely head over clarinet crushing on Karkat, despite his glaringly obvious interest in Terezi (who was either completely uninterested, or sympathetic but not reciprocating). But you just did nothing, and when summer rolled around again the only plus side to still having such a major crush was that at least your blush was hidden by the heat-induced flush.
Sophomore year passed much the same as freshman year, though you did try dating Equius for about a week before realizing it felt too weird. So when you guys returned to being friends, you decided to clue Equius in on who it was you really were into. He actually approved, which was good considering he was still your best friend, and offered to help you woo the oblivious Vantas.
You declined, and spent almost all of sophomore year pining. You did, at least, put a little anonymous note in Karkat's school locker asking him out to the Girl's Choice dance. You'd marked it with a little paw print, a sort of clue for Karkat to help him figure it out. He'd ended up showing the note to Terezi, who'd given you a pitying look, asking her if she'd written it. She'd told him no, and gone on to ask Vriska to the dance.
And you'd gone into that year's summer band with a lovesick heart.
The fall of junior year you spend working up the courage to ask Karkat out to prom. This was the first year you could go without an invite from an upperclassman, and you were determined to go with that stupid, grouchy albino. Equius helped you practice, and you felt like you were ready right around Valentine's Day.
Armed with a little orange tulip, you went to school that day with your courage wrapped around you tightly. When you found Karkat, he was in the band room telling Sollux that he was swearing off prom this year. Turns out Terezi had rejected him that morning. Optimism shattered, you tossed the flower in the trashcan. You spent prom with Equius watching movies at his house.
That summer you tried avoiding Karkat, but he always seemed to seek you out during breaks. Eventually you were so sick at heart of his innocent and gruffly worded questions that you had Equius run intervention for you. Senior year, you vowed, would be the year you got over Karkat Vantas.
You didn't attend any of the fall dances, and you got yourself involved in a couple other extracurricular activities. Equius got you a cat themed beanie for your birthday, which you wore when it started to get cold and even when it snowed. Your whole friend group (minus Feferi, Eridan, and Gamzee, who had all graduated) got together to play in the snow, knowing it wouldn't last long. Sollux made a few jokes about losing Karkat in the snow, and that eventually devolved into an eight-man snowball fight.
Classes started up again in January, bringing you back into contact with Karkat. It was a lot more painful after the three-week break (which you had spend out of state visiting family), and every conversation was like a knife in your heart. And then it was Valentine's Day, and you very matter-of-factly got everyone a corny little cat-themed valentine (though your heart raced when you gave Karkat his, and the way his face lit up with one of his short-lasting grins almost tore you in two).
You didn't ask anyone to prom, you didn't plan on going to prom, and really that was okay. Equius had mentioned hosting another movie marathon at his house, since he hadn't been asked or asked anyone himself, and that seemed really nice. You would enjoy that. You didn't need to go to prom, after all.
Except, the afternoon you were going to commit to going to Equius' house, you found a crumpled little note in your locker asking you to a private meeting after school. You talked it over with Equius, and with the assurance he'd be right outside the doors of the room you were supposed to go to, you decided to go after all.
No one was there, though there was a letter on the table. Attached were tickets and a very gruffly worded invitation to prom, signed with a little frowning face. And you cried, and you dragged Equius to the band hall. "Karkat!" You called, wiping tears from your face. "Karkat!"
He poked his head out of one of the practice rooms, face bright red with embarrassment. "Hey, Nepeta. You get my note?"
"I did," Nepeta said, smiling just like she'd done back on first day of summer band. "I'd love to go with you to prom."