Anger. That's what he felt. It's an emotion he felt frequently, perhaps too frequently, since his un-evolved state was revealed. The anger he felt then and there, however, was different.
The burning, desperate, fury coursing through him as he held his burnt and soggy notebook made his head ache and his hands tremble. He was pathetic, helpless, and unable to even raise his voice to his once childhood friend. Worthless. Quirkless. Oh, that fury burned brighter than the flames his no-good, deserting father used to blow.
He knew, of course he knew, a person like him becoming a hero was a long-shot. A wistful dream from his childhood for his nearing future. But he could dream, damn it all. Why couldn't Kacchan let him dream?
By the time he made it home it was dusk. Not nearing dusk— it was dusk and long after his mother expected him home. Though any other time he'd be spilling apologies and promising to make it up to her, he was too tired to pay her worried expression much mind. He closed his bedroom door on her concerned questions, like the stressed teenager he was, and dropped ungracefully on his bed. What an eventful day.
Not even an hour after fishing his notebook out of the water Izuku met All Might. He met his all-time favorite hero, the nations Symbol of Peace, and the man's frailer alter ego. He met his hero and, as angry as he was, he couldn't even enjoy it. Nearly dying via slime monster did little to cure his anger it seemed. Neither did being told he's not hero material by the very hero he wanted to resemble.
Saving Kacchan hadn't been a conscious decision. Honestly, what was he thinking. Did he want Kacchan dead? No. No, of course not. An asshole he might be but he didn't deserve to be a dead one. Still, there were plenty of heroes on the scene, All Might included if his timely intervention was anything to go by. So why, why, did his stupid legs run him toward the danger? According to the heroes, and his own common sense, damn it, he was lucky to make it out alive.
The walls of Izuku's room were plastered with hero posters. All Might's grinning, dream-crushing face hung everywhere. The thought of All Might's well-meant parting, "You did well, Young Man, but please keep yourself safe. Leave things to the professional heroes," sent a pulse of blinding resent end up his spine.
Brightly colored, glossy paper crinkled in his hand. He pulled it and it ripped. Tatters of poster fluttered down around him in a sad mockery of autumn leafs. He wanted to be a hero. He's always wanted to be a hero!
He everyone to live in peace. He wanted to keep people safe. He wanted to save people!
He didn't want to be weak and helpless— quirkless. He didn't want to be the one saved!
The walls of Izuku's room were bare save the small poster corners stubbornly stuck with tac. His floor was a mess and so was he. He was still so, so angry— at himself and at the world. Perhaps he let his anger fester for too long.
He wondered if his mother heard his rampage. He didn't recall making a sound but, to be fair, the whole event was a bit fuzzy.
Once more, Izuku fell to his bed. Exhaustion finally took a heavy hold on his body. Being a hero, though once a long-shot, seemed little more than a speck on the horizon. A speck that might only be a mirage. As he drifted to sleep on top of the covers he couldn't help but wonder— did he even want to be a hero anymore? Obviously he had some things to think on.