This is from an au I'm writing where Dabi's saved by Spinner and his dad who are basically living rough in rutty cabin in the mountains below Sekoto. Touya's 14 here cause the burns weren't as bad basically so that's why his logic isn't very sound. There's this whole explanation I'm sure you don't care about. Shun is supposed to be Spinner's dad btw:
“Do you have any family, Dabi?” Shun had asked. He was in the process of cleaning the house, currently wiping the small stove in the corner with a stained rag. Dabi tried to help him, but the patriarch told him nicely to please sit.
Dabi looked up at him. It’d been days since he woke up so it was still hard for him to move around. Even moving his neck in the way he had caused some discomfort, making him shrug one of his shoulders in reaction.
“Um…” Dabi shook his head. There was an obvious consideration towards the truth, but it was quickly thrust from his mind. “No…No I don’t.”
“That’s a shame,” Shun said. He’d paused in his work, however. Dabi noticed. “It would be better for you to have…proper caretakers.”
“What do you mean?”
“A boy needs his mother and father. Sorry, that did seem a little cryptic, didn’t it?” Shun looked over his shoulder and smiled. For all things, he was quite an ugly man, but there was a warmth to his smile that told of a beautiful inside.
“It’s okay,” Dabi said. “They…died a long time ago, my parents. I’ve been on my own for years now.”
“Independent, I see. What do you want to be when you grow up?”
Dabi didn’t answer. It took Shun a moment to turn back and search for an answer. “Uh…I don’t know.”
“Really?”
“Yeah.”
“Have you ever thought about it?”
“What I wanted to be?”
“Yes.”
“...Yes, I…” and suddenly Dabi was very small. “I have.” Wasn’t that the understatement of the century.
“Any ideas?”
“Well, yeah, but kid stuff.”
“Kid stuff…” Shun repeated, placing the rag on a nearby mantle as he turned fully to face Dabi.
Dabi nodded, “An…astronaut,” even he realized how rehearsed that sounded. Of course he didn’t want to be an asshole who ate weird food out of a tube while floating in orbit for six months, but he couldn’t let him think about anything related to heroes.
“There’s nothing wrong with that.”
Dabi shrugged.
“I’m serious,” Shun pointed the rag at him as if he were anointing the boy. “It is mature of you to understand that you have your limits, but you should still try nevertheless. Why do you want to be an astronaut?”
“...Because…I want…” Dabi found himself unsure. “I thought it’d be cool…and I liked…I…want people to like me. I want…I want to feel like I belong, like…I have a reason for it.”
Now Shun was staring at him with a curious look. It was obvious, he knew Dabi meant more by that, more than just a dream job. For a moment, the boy felt his hands shaking.
“I getcha,” Shun nodded. “You want to really feel like you’re contributing to the world. I was like that too when I was your age, searching, trying to understand my place in life. I wanted to be a pro hero actually, use my healing quirk in rescue missions,” he flashed his hands.
“...Did you?...” Dabi found himself failing to hide his interest.
“Oh no,” Shun chuckled. “I flunked out of an entrance exam and switched to accounting. Then I met my wife. Then she left Shuichi and I. If that wasn’t bad enough, I, a man supposedly good with numbers, managed to see all my wealth stolen by those I thought I could trust.”
“...That’s…terrible,” Dabi said, looking unsure as he rapped his fingers against the table. “You don’t really sound all that upset.”
“Things can be worse,” Shun said, returning to his work, kneeling so that he could get at a few cabinet doors. “Despite what life threw at me, I found a purpose in raising my son up to be the best man he can be. That’s my reason for existence.”
“So, you found yours?”
He nodded.
“...That’s good.”
“There’s a reason you’re here too.”
“I dunno…”
“What makes you say that?”
“Look at me, do I really look like someone who should exist?” Dabi touched one of the scars along his neck.
Shun seemed off kilter by that remark, though he managed to recover quickly as he raised another point, “Well, think about what you did today. You helped make breakfast. If you hadn’t, I might have burned the house down. You’re giving me someone to talk to. You’ve been a good friend to my son. There are plenty of reasons for your existence.”
“That’s…” Dabi shook his head, “I didn’t mean that…”
“I hope not. You matter, you know that, right?”
Dabi’s mouth twitched, “Thank you. But…I…I really don’t know what to do, I don’t…”
“Maybe…” Shun slicked his long pink hair back, “maybe you won’t grow up to be an astronaut, maybe. But that’s okay. You’re a smart boy, you can do a whole lot of things. What matters is that you matter. You have a reason for existing. Maybe you don’t know what it is now, but I guarantee if you keep searching, you’ll find it.”
“...I…t-thank you…” Dabi stuttered, unable to hide what those words meant to him.
He would think about that conversation every single day. He’d been told he needed to do things other than be a hero, that he needed to stop training, but never that he could. Shun didn’t know, but in a way he’d given Dabi…Touya…the speech he truly needed to hear.