Setsuna Hanabi MV Theory
This took a lot of rewatches but I think the mv isn't linear. So we're just getting different pieces strung together. This would probably mean Yeonjun survived the crash bcs he only has the injuries while in the outfit in the opening scene and he's explaining he almost died. Becuase one of his creditors(?) cut the brakes of his bike prossibly because of that fight they had near the beginning of the mv. I think they're all trying to find their place in life. Yeonjun with his thrill-seeking (riding). {Also very very minor side note this kind of reminds me of the BSD scene where Dazai is telling Atsushi he'd like to go as beautifully as a firework.) Obviously in this timeline Yeonjun isn't dead but that's some interesting imagery of a life that burns as beautiful and bright as a burning firework (I will interpret this along the line of passion and desire bcs we see Yeonjun give Taehyun the keys so perhaps he's taking a break from racing and perhaps passing it onto Taehyun(?)
The next most explored person is Soobin, his mentor/father figure was the one who owned the repair shop. Yeonjun and Soobin probably met during that one Yeonbin scene on the bridge bcs it looked like Yeonjuns bike had a breakdown hence he calls a nearby mechanic shop (I'm assuming Soobin fixes at a very low rate cause they all look broke) and they met. Idrk how the other fit in together but I think the closest and the ones who first met are Yeonbin. And in the opening I think Soobin is fixing the bike that the creditors broke mid mv
Next we have Hyuka at a job interview. I think this is what they're later celebrating by drinking bcs he's wearing the same clothes (I'm also going to take this as he was accepted). The Kendo (?) scene seems to be more like Kai's perception. How he's viewing the questions in the interview and I do think he didn't succeed (because he was looking rlly out of it in that one scene where and office worker (?) bumped into him. This also means he's trying to conserve a small bout of hope for the group so they can try to celebrate his success (though he didn't actually make it). I think him falling down against his opponent also signifies this. Idk if Kendo is supposed to be a part of his character but it does feel like it's more of a representation bcs it would make sense. He's fighting for a position against others he doesn't know (other interviewees). I also think he might have had a passion for the sport which he's translating into the interview bcs though he doesn't want a corporate job he needs it and he'd rather have his game face on for it
Beomgyu seems to be an unsuccessful musician. Either that he lost contact with the rest of his bandmates (this is an interesting callback to real life Beomgyu bcs though he got into a group it wasn't exactly a band). We can also see him playing a guitar in the beginning of the mv asw. The MOA sign kinda seems like he's longing for MOA. I feel like we can interpret this as him longing for fans to consume his work. So I think he feels like he's in a dump bcs of that
Taehyun had the least context of this. Couple of things tho is that he has violent self destructive tendencies (of he was js being edgy) and he also had a forehead injury which could be by falling or by banging his head. The next few times we see him he's escaping the hospital and also being with the group. I do think it's interesting he's the only member shown with a specific material belonging. I feel like the watch associates some wealth to him along with the fact that it looks like a nice private hospital. I feel like Taehyuns story revolves more around him finding a purpose (as does Kai and Beomgyu) bcs hes already rich (the other two aren't shown to be so tho) whereas Yeonbin are fully just trying to survive. They're story is entirely revolving around debt and conflict.
I think the final shot is a flashback to a happier time, through Yeonjuns eyes bcs there's only 4 members and we saw that was moments after he got in an accident. I feel like its the mini flashback to a happier moment he had b4 his supposed 'death'. But we know he survives bcs of the beginning
[This is basically a copy paste from a comment I made, also apologies for the typos]