You had been working alongside Deku, the current #1 Pro Hero in all of Japan. But he is no longer the bright-eyed hero loving boy he used to be. He has become more solemn and quiet, knowing the truth of heroes and even feeling a bit dejected towards hero society as a whole. But he still does his job well, he never stops working even if he's injured. He appears to be the 'perfect' hero, but you know better - you know he breaks down the moment he thinks he's alone, the stress often getting to him.
It's been ten years since the war ended, and he suddenly takes the day off. You follow behind him, his mind focused as he walks to Kacchan's grave. He places an All Might card on the grave, before crumbling to his knees and gripping the headstone while his tears spill out like a waterfall.
"Kacchan...we were supposed to be #1 together. You were supposed to be by my side, fighting with me. I...I'm so sorry..."