@aavaros-aaravos wanted to know the appeal behind Tadashi/Reki so here I am!
Also this doesn't have to be taken in a shipping way, but if you want to that is totally fine! I personally don't ship them but people can do whatever they want.
So where do I find the appeal of their dynamic? Well pulling from the show parallels show that Reki most likely shared a lot of similarities to Adam when he was younger. Of course Adam appears to be much younger in the flashbacks but if it wasn't for... everything I think he would have grown to be some sort of balance between Reki and Langa (after all I could totally see Reki growing into the theatrics Adam has going on).
This isn't really about their similarities though. Instead I'm going to present how I would go about writing their dynamic since outside of a shipping sense (which is mainly nsfw content :/ ) I don't see a ton of their dynamic.
So let me present this to you!
Reki and Tadashi formally meet in the Love Hotel which yknow... amazing content for the shipping side of this lol, but —
Tadashi says some stuff there. He tells Reki to drop skateboarding. He tells him about the reputation skateboarders have as delinquents (which I think that this is definitely a jab at younger Joe, Adam, and Cherry) and how people generally don't make money off of it and can get seriously injured. His entire conversation with Reki is very similar to what Joe says to Langa before their beef, but while Joe clearly loves skating, Tadashi holds resentment towards it (my Tadashi/Joe shipping heart adores these parallels).
Anyway they have taken a character (Reki) who is on the verge of giving up skateboarding — something that makes him so happy — and put him in a room with someone that agrees with him. Then Reki disagrees with him. I love that.
Reki disagrees with him and tells him how awesome skateboarding is and has a passion for it that clearly Adam has/had but also a passion that Tadashi probably had at some point too.
Tadashi doesn't change his stance (obviously) but I got the sense that their was a hint of agreement in his eyes. That, yeah, his experience has been less then wonderful, but there was a time when he loved this too.
When Tadashi is handing Reki his invitation for the tournament it is hard to say if he is worried for Reki’s sake or worried that Adam will do something that could gain press (I suspect that it has more to do with Adam, but maybe it could be seen as a bit of both?). Anyway he tries to get Reki to decline and we all know how that goes.
By the end of the race Reki lost but Tadashi dropped out and let Langa take his place.
Let me just say: I hated that. I understand that they didn't have the time to have Tadashi race Langa, but the impact on Tadashi and Adams relationship? It would have been crazy to watch the two race and when we do get new content I hope we get to see more of the two skating together. While Tadashi had different motives for trying to race against Adam (taking it away) by the end of Reki and Adam’s race he has decided that Langa could teach Adam how to have fun... so his motivations have changed yet he still believes that Langa is better suited for the job???? What?
Anyway side rant over (sorta?) because when you think about it. With Reki and Joe out of the race Langa was better suited for the job because Tadashi doesn't have fun skating the way Langa does. (I just would have loved to see the impact on their relationship/dynamic if they had raced 😅)
Anyway after the show it is very much up in the air if Tadashi would ever want to attend S again or be around the others. He doesn't seem all that invested outside of Adam’s happiness/reputation— 🤔😏
So I like to believe that as Adam gets better and all that jazz he wants Tadashi included more because he wants to see Tadashi have fun too. The problem is that Adam can't seem to get Tadashi genuinely invested the way they used to be. He asks Langa about it and — when by some miracle the two idiots decide that a beef isn't the answer here — Langa decides that if there is any chance of Tadashi enjoying skateboarding again it is going to happen thanks to Reki.
So Adam asks Tadashi to give Reki pointers since, "Sorry pup, but I can't be bothered with the little Red. Snow bunny isn't really a teacher and I would lose my patience!"
Tadashi agrees since who is he to disagree with his master?
It feels like a chore. It feels like more work because it is more work. Reki catches on quickly too (especially since as of right now he isn't interested in an actual teacher).
Reki makes the claim that, "you don't actually want to be here man."
For whatever reason Tadashi tries to disagree (the "whatever reason" being that Adam asked him to keep the boy happy).
Reki sees through his bullshit and while he doesn't fight on it he has a new goal in mind: "if you are going to teach me to skate then I want you to enjoy it!" His new goal becomes making Tadashi like skating again.
Maybe Tadashi does and maybe he doesn't, but being around Reki certainly can be... enjoyable.
Okay this was a long post so to make a long story short: Reki is to Tadashi what Joe probably was to Adam.