As much as Izuku tried seeing the best of anything there were actually a lot things he really didn't like. Kacchan looking exhausted both physically and mentally was probably number one on the list. And knowing it was his fault? He would be fidgeting with guilt if he could move his lower body. As it was he just watched as Kacchan dragged a chair closer and sat down on it looking at him like he was this close to chewing him out. The silence became uncomfortable when Izuku realized he was supposed to say something.
"Kacchan I'm so-"
"Don't-" Kacchan interrupted him with a glare something fierce "-shitty nerd don't apologize. We both know you will be throwing your stupid self the next time you get the chance." He said with a mix of anger and exasperation in his voice. Izuku desperately wanted to make him smile. But Kacchan felt far away in that tiny hospital room. He looked untouchable.
"Kacchan," Izuku started in a shaky voice, "I'm gonna be better, next time I will not break." He said. Don't worry about me, he didn't say. He was sure Kacchan read it in his eyes before he even thought it. So he smiled and watched as the hot headed hero climbed to his feet. Before he could ask him where he was going Kacchan was in the tiny hospital bed with him, trying to cover himself under the same quilt, lending his warmth to Izuku's chilled insides. An awfully big grin was fighting his lips for control but he knew he made Kacchan mad enough as it was. So he didn't comment didn't react more than making room for him to get comfortable. A few turns and seconds after Izuku was on his back and Kacchan had his head on his chest, close to his heart. Izuku had to bite through his lips to stop his tears from welling up, the implications that he scared the other hero that much hitting him hard.
A few seconds were spent in silence with two boys just laying and it was still uncomfortable. And so Izuku decided to sing.
You have my heart and we'll never be worlds apart
Maybe in magazines but you'll still be my star
Katsuki flinched slightly when he began singing but soon he released the tension he had in his muscles letting himself to Izuku's song. He loved singing this one. Because to him it fit well for them. Even before Izuku knew what a heart was for it belonged to Kacchan and he would never be ashamed of saying it so. And of course Ground Zero was his number one hero.
Once, Izuku recalled, they went to drink with Tokoyami-kun and Ochaka-chan and before he knew it he had to take care of three drunk people and Kacchan demanded rather loudly that he sing. So, to placate him -because a drunk Kacchan was even more prone to explosions than the sober one-, Izuku began softly singing. And Kacchan actually complimented his skills - a big surprise- with a set of curses and insults of course-not really a surprise. Then so it became their thing. When Kacchan was restless Izuku would just hum a melody just low enough for him to hear and for a minute they would be alright.
So Izuku sang.
So Izuku sang the "I love you"s that Kacchan would blow him up for in a way that meant a lot to both of them. So he sang to make sure Kacchan knew he was right here, not going anywhere even if he was stupid enough to jump in front of enemies.
Said I'll always be your friend
Took an oath I'm a stick it out till the end,
His voice wavered when Kacchan turned his head just a little, enough to make Izuku feel lips on his skin. Burning through his chest and branding his heart anew. And moving slightly, too. Joining him in his song, in some way, making Izuku smile, making it harder for him to sing. He was the one supposed to make Kacchan feel better but Kacchan was best at everything wasn't he? So he raised a trembling hand and ran it through blonde hair that he loved so much, desperate to pay back all the love and care he was given till his heart ran out. And maybe the only thing in it would be Kacchan, Kacchan, Kacc-
You're part of my entity,