The last note hung in the air after Iruka strummed the guitar one final time.
He looked up expectantly at his friends. “Well?”
One beat, two - Iruka flushed inadvertently at their silence. He wasn’t a musical prodigy to be so assured that all the songs he composed would be a hit. Despite having them be the first to listen to his every song, the act of letting his friends hear the first draft, raw and unpolished, was intimate enough to send that fissure of uncertainty through him every time.
Besides, the composition was honestly a bit bare-bones. He had spent the last week obsessing over it, plucking at the guitar strings and singing the notes over and over, but still. Bare-bones.
Kotetsu sighed, sending the worst of Iruka’s insecurities caterwauling through his head.
“Man,” he said gravely. “You’ve got it bad.”
Iruka blinked. “What?”
“He’s got it so bad.” Kotetsu turned to the drummer of their group. “C’mon, Izumo. Tell me I’m wrong.”
Izumo shook his head. “It’s good,” he said and utterly betrayed Iruka when he added, “Kotetsu’s right, though. You’ve got it bad.”
“I don’t know what you mean,” Iruka spluttered. “Look - I wanted your opinion on the song -”
“I said it was good - “
“- not my love life!” Iruka threw his hands up into the air. He turned to glare at Anko who had yet to say anything. “Do you have any comments to add?”
“Izumo’s right, it’s good,” Anko admitted easily. Iruka couldn’t help but feel inadvertently pleased - Anko was a harsh but fair critic, and never hesitated to let him know better. “Real good. The refrain’s catchy, and the bridge’s got that wistful tinge when you repeat it slow.”
“Right?” He interjected excitedly. “That’s exactly what I was going for -”
“And,” she continued, and Iruka should have known better. He should have known better, especially when that shit-eating grin graced her face. “If you wanted everyone to know about your crush on Hatake, here it is! In song and rhyme.”
Iruka groaned, long and loud. “I didn’t even describe him!”
It was a losing battle when it came to his crushes - Kotetsu was a meerkat on the lookout for the slightest hint of any interest Iruka showed in anyone, while Anko was the bloodhound that would gleefully chase those traces down. Paired together, they were a formidable force.
Easier to admit to a crush than to face their endless receipts for when he was looking at who, how and why.
“You guys are projecting,” he emphasised. That was the reasonable explanation for the madness he was going through. “Projecting, I tell you!”
“Are we now,” Anko said archly, before singing his own words right back at him: “Lights in my eyes, but all I see is you - “
Kotetsu gleefully jumped in with an entirely separate verse, “Caught by surprise while the fireworks they bloomed -”
And the terrible traitor that was Izumo joined in, straight to the refrain: “The stars they burn, the stars they shine, yet still I’ll never reach them in time - how could it be about anybody but Hatake?”
“People write about lights, fireworks and stars all the time!” Iruka protested, saying absolutely nothing about how Kakashi had been sitting in the front row and Iruka had looked at nobody else but him. It was fortunate that despite being their group’s primary songwriter, he was content to be the bassist - and the backing vocals for Anko if really need be.
Usually that happened when Kotetsu went too hard on his saxophone solos. Which was more often than not.
The point was, no one was looking at him when they could look at the absolute balls of energy that were Anko and Kotetsu, and so no one saw him blush when Kakashi looked straight back at him.
And then looked away just as quickly, because what was another band’s bassist to him? It’s not as though he looked at Iruka when he was performing either. He was professional that way.
“Sure they do,” Kotetsu said all too patronisingly. “Look, I swear if Hatake isn’t aware of your massive crush on him after we perform this song, then he’s just as bad as you.”
“I think he is, actually,” Izumo added thoughtfully. “Iruka’s been making eyes at him - “
“Doesn’t help if he’s looking away when Iruka’s looking,” Anko scoffed. “He’s as bad as Iruka, I’m sure of that .”
Or so they keep saying, but the one time Iruka approached him - not even to ask him out, but to ask for an extra guitar pick - Kakashi had shoved one at him and ran off. This wasn’t a goddamn TV series, Iruka could tell when someone was not interested in him - hell, maybe Kakashi was one of those instrument snobs who believed in using fingers over picks.
Still, the pick Kakashi had given him looked kind of worn, a silvery-white slip of a thing. It was holding up pretty well too - it hadn’t broken on him at least. Come to think of it, he was using it now.
“Just as bad,” Kotetsu echoed, waggling his eyebrows at Iruka knowingly.
“Guys, can we please talk about the song?” There was an entire cycle of grief to be had with Kotetsu, but Iruka found it fastest to skip past denial and straight into bargaining. “Please? We have two weeks to workshop this.”
“Iruka’s right.” Thank the gods, Izumo had finally gotten off the gossip train. Either that or he took pity on Iruka. “I think we can use this. It’d be a good entry. It might even blow the judges out of the water.”
“Might even get Hatake to get off his ass,” Anko laughed raucously. “He can’t look away from a song like this. He’d have to use earplugs.”
“Oh, gods no,” Kotetsu said in mock horror. “If he uses earplugs he’d be the human equivalent of those three monkeys - “
“What three monkeys,” Izumo asked.
“- you know, the one that has their hands on their faces. Like see no evil, hear no evil, say no evil - wait, he’d be seeing some evil - his eyepatch covers only one eye.”
Iruka let out a long sigh. That was terrible. Kotetsu was terrible.
“You’re terrible, and I hope you know that,” he informed Kotetsu solemnly.
Kotetsu nodded, unrepentant. “You’re right, I’m the one bearing the burden of being the funniest one in this group.”
“Just like how we all bear the burden of watching Iruka and Hatake dance around each other.” Anko rolled her eyes, getting onto her feet. “Let’s get this show on the road.”
Kotetsu and Izumo scrambled to their feet, their demeanours shifting to something more serious - playtime was over. For all their teasing and Kotetsu’s dramatic and periodic accusations of Iruka consorting with the enemy, they wanted to win. They all wanted to win.
Iruka’s feelings for Kakashi whether they were glaringly obvious or not wouldn’t get in the way of that. But he could use it. Just as fuel, just a bit. And if it got Kakashi to keep his gaze on Iruka, well…
Iruka wouldn’t mind that either.
trope as suggested by @myka1231. The appeal is endless: the bright spotlight that puts the singer - and all of their emotions - on a display that cannot be ignored, the strings that hum beneath their flying fingers, or the feeling of circling round on a song that has yet to be formed - that is, until the writer meets the right person. 
trope as suggested by @Dunloth! Oblivious idiots who are so very in love. They swoon, they sigh, they deny it (oh-oh), but everyone with eyes around them can see it for miles. It makes you want to push them into a locked room until they admit the truth to each other (and take that relationship to cavity-inducing levels.) 
It was amazing!
amazing art for Rock Band AUs indeed!