AN: Hello all! Welcome back to another little My Hero idea that popped into my head and said, 'write me', refusing to leave until I did so. This little nugget came about when I considered something. Izuku was bullied and never stood up for himself because he had no confidence but let's look at something.
There was a 10 month window where Izuku was being trained by All Might and was still in school with Bakugo
Izuku was shown having become strong enough, not that far into the training if my reading of the situation is right, to actually do a mile run or something with a full sized All Might on his back.
He was getting personally trained BY All Might, the crem de la crem of heroes, Izuku's personal idol
So, those things all together could quite easily help build up Izuku's confidence, especially if this world's All Might had some brain cells remaining in that thick skull that weren't killed off by inhaling excessive hair spray and taught Izuku how to throw a punch or two. So, we get this piece here, enjoy!
Head held high, Izuku couldn't hide his grin as he walked to his homeroom for the first day back at school after the Winter Vacation, the entire time he'd spent training with All Might to be able to properly use One for All, as well as what came after. As he walked to class, he noticed his various school mates taking notice of the fact that he 'was so much taller', the fact that he'd stopped slumping and walking hunched over probably helping with that.
"Well, well, what have we here?" hearing a smug nasally voice, Izuku looked up to see two of Kachan's lackies, the fat one with wings and the skinny one who could extend his fingers, sneering down at him, "Someone's looking a little happier than they should be."
"Why, he might even be thinking of ignoring Bakugo's orders to give up on his dumb dream to be a Hero." Crony number two snickered, extending his fingers in what was likely supposed to be an 'ominous' gesture only let out a surprised gasp when Izuku grabbed said digits and squeezed.
"You know, extending your fingers like this just makes them more of a target, more fragile, more ways they could break." Izuku kept up his smile as he spoke, knowing these two were followers at best and pretty cowardly at the slightest hint of someone showing any resistance. Without Bakugo around to back them up they'd fold like a house of cards in the wind.
"You'll regret this!" Fingers shrunk his fingers back down and ran away, Wings followed after, huffing at having to move as fast as he was.
"Huh…that was…easy." Izuku frowned, wondering if his life might not have sucked as much over the years if he'd stood up to them a long time ago, "Oh well, I still have class to get to." Whistling cheerfully to himself, and pointedly ignoring the wide-eyed stares from everyone seeing the Aldera Middle School Punching Bag, trademark certified, standing up for himself.
Sitting in class, Izuku tapped his pencil against his bottom lip, a new blank journal in the desk as he was jotting down various thoughts of what he could study to improve his ability as a hero. "DEKU!" hearing the explosive shouting of his childhood friend, and mentally noting to add special awareness to his list, he looked up to see the angry explosion wielder glaring at him "I thought I told you to get rid of those damn Hero Journals!"
"This is a self-improvement Journal actually Kachan." Izuku flipped through the pages to show most were blank and it was full of exercise plans and dietary patterns. Seeing the crackling of small explosions in the blond's hands, Izuku rapidly moved the journal away before it could be grabbed "I'm not letting you destroy another Journal Kachan." Izuku said firmly, eyes narrowed at the boy, time with All Might flashing through his head, the man encouraging him, telling him to stand up for himself.
"All of you, sit down already!" the teacher snapped, stopping the altercation before anyone could move any further.
"We'll be having words Deku, just you wait." Kachan snarled as he took his seat. The class went by painfully slow as Kachan seemed more focused on glaring at Izuku than actually paying attention to the lecture, getting only more incensed as Izuku kept his focus on the teacher and the notes he was taking. When the bell rang for Lunch, Izuku was positive that to most of the class it was like an announcer's bell to begin a boxing match, the teacher leaving without even a care at the clearly tense atmosphere, the impending violence a blind man could see.
"Fingers, Wings, block the door." Kachan snarled, standing up to tower over the still sitting Izuku, the two lackies happily doing so as they smirked smugly at Izuku now that they had backup. The others in the class all stood back to watch the upcoming fight.
"You don't want to do this Kachan." Izuku sighed, wanting to give his childhood friend one more chance for the memory of the close bond they used to have.
"Oh, I really think I do." Kachan…no, Bakugo smirked, grabbing Izuku's brand new journal and toasting it between his hands. Carelessly tossing the now charred and ruined journal over his shoulder, Bakugo reached out with the still crackling palm, a sick and eager grin on his face that Izuku was ashamed he'd ever though was heroic before.
"I warned you." Izuku surged up, catching Bakugo off guard with the unexpected action and threw a hard punch into his tormentor's gut, doubling the blond over as Bakugo wheezed for air. The powerful muscles that Izuku had been developing over the months of training making their 'debut'. Slinging his bag over his shoulder, Izuku walked past the snarling Bakugo and towards the door where the two lackies stood gaping. Keeping an eye on their eyes, Izuku was prepared when Bakugo attacked from behind, the right hook the blond always used still present as Izuku reacted, throwing Bakugo over his shoulder hard, slamming his tormentor into the ground before giving a hard kick to his stomach. Leaving the now downed bully, Izuku moved on to the door again where Bakugo's cronies still stood.
"Y-you're not going anywhere!" Fingers stammered, trying to look tough, and likely hoping they could delay him long enough for Bakugo to get up.
"Listen here, I'm done being your punching bag." Izuku gave them both a hard stare "So I'd suggest you get out of my way."
"W…we'll report you!" wings shouted desperately.
"Yes, report how you helped Bakugo attack me with his quirk, a serious crime." Izuku snorted "Report how me, a 'quirkless nobody' as you like to put it, kicked the ass of Aldera's resident demolition expert. You saw what I did to Bakugo, so I'd suggest you get the hell out of my way, and leave me alone." Izuku gave them a fierce glare as the two trembled and backed off, all those watching parting out of his way as he made his way to Lunch.
AN: Like I said, a simple idea. I might turn it into its own fic at some point, or someone can adopt it. Either way, I thought it was a neat idea.