To be honest, Smokey was expecting Mikado to completely brush off or even refuse his apology. So when his teammate actually accepts it (albeit in his own roundabout way), Smokey's eyebrow rises in surprise. He doesn't say anything in response, though, mostly because he doesn't really know what to say. He wasn't expecting to get this far!
Unfortunately, not saying anything gives Mikado the opportunity to drudge up another bad memory. Smokey's brow furrows and his face contorts into a scowl as he recalls the event in question; they had literally just landed and one of the first people the group met was a person from his past. And in only a matter of seconds, Smokey regressed back to the child he was before he'd left for beacon, barely able to restrain himself from violence.
It's a long silence before Smokey actually responds to Mikado, "That's, uh, that's a long story." Another awkward silence follows as the two continue walking in the summer heat. Eventually, though, Smokey breaks the silence with a sigh. "You're not far off, though. That guy and I go pretty far back, but it's not really a fun story," he says, staring at the sidewalk as he speaks.
"Believe it or not, I didn't really have a lot of friends growing up. I used to get real mad real easy-- hell, I'd deck ya' if you so much as looked at me the wrong way at one point," he continues, staring off into the distance as he recounts his past, his fists clenched in his pockets. "Problem was, I was also real scrawny at the time, and all the other kids were bigger than me, so it wasn't a problem for them to kick my ass. Once they figured that out, it just kinda became a game: see how fast 'Mt. Shortstack' could blow his top, then make him eat dirt." He pauses for a moment to give a bitter laugh and then adds, "They got away with it, too, 'cuz I was always the one that threw the first punch."
"Verde, that guy in Atlas? He was one of the worst. Growin' up he was one of the biggest kids around 'cuz he started school late or something. On top of that, he always knew exactly what to say to get my goat. Hell, guy wouldn't even let ya' walk away, either, 'cuz he'd always have his posse backing him up and surrounding you. So, I ended up doing exactly what he was trying to get me to do: I threw a punch. And then he'd lay me out on the ground, his buddies would kick me a couple times, and we'd all go home for the day. I'd just have a few extra 'souvenirs'."
He continues walking in silence for a bit after that, before shaking his head and stating with a sarcastic chuckle, "Three guesses why I chose Beacon over Atlas."