Bakugou uses his quirk too much along with yelling all the time so he's used to loud noises. One day after training he wasn't paying any mind to the “extras” and left the changing room going back to the class that's when kirishima's tapped him and he yelled at him or at least he thought he didn't hear himself yell he saw kirishima's mouth move and his hands wave like an idiot but heard nothing

”Bakugou: dumbass speak up!?” *I yelled but I still can't hear myself ’what's going on’ I think as my eyes widen as I place a hand on my ear and mumbles for the first time anyone's heard

’Bakugou: shut up dumbass…stop talking to me when I can't hear your shitty voice…” I started panicking when I realize I can't hear anything or anyone everyone looked confused and was saying shit but I just shove them off not even yelling as I started panicking internally confused and not wanting to admit it but I was a bit scared