Nagisa has special Keet-induced superpowers of luck.
Everything he wants seems to magically go his way. He was able to get Rei, who didn't even know how to swim, to join the swim team. He was able to save him with seemingly less hassle than Haru did for Makoto, even though Rei was the one drowning in the first place and
we see a giant wave crashing on top of them. The wave was then never mentioned again. Finally, whenever he suggests some kind of arrangement for the others, it always goes exactly how he wanted no matter what the others do. For instance, he wanted to sleep in the same tent as Haru, and he wanted Rei to check the fridge, and that's what ends up happening even though they decided to leave it up to luck.
- Or maybe he's a Keet precisely because he's so lucky. Maybe he's never had reason to be actually unhappy in his entire life, since he ends up getting whatever he wants.
Rin is dead/a ghost.
He died shortly after returning to Australia for the first time. His ghost is haunting the members of his swim team, who feel responsible for his death.
Or half-Selkie, at least. Perhaps his mother returned to sea, and that's why he seems to live alone? His obsession with water is due to longing for his home, and his trouble with relating to others comes of not being quite their species.
- Wouldn't a kappa be more likely?
- Nah, 'cos we've seen him lie down... his dish would empty, if he was a kappa, wouldn't it?
- Also, kappas are polite. Haruka is...not.
- Perhaps one of his parents is/was a mermaid/man who are either splash-style mermaids or became human through the little mermaid method. While Haruka didn't inherit the tail, he still has the love of water.
- Or now that it's out, Haruka can be a mer-person from Nagi No Asukara. And unlike the merpeople there, Haruka found a way to live in the land just fine but soaks himself with water as an old habit to replenish is raiment.
The boy with shark teeth in the photo that Rin took from the old swimming club is his father
In "High Speed", there are pictures at the swim club dating back 23 years. Rin is the only character shown to have shark-like teeth, and as shown in official material, his father is absent.
- They all have brown hair, green eyes, similar hairstyles, and pretty boy features. Their animes are all produced by the same company as well. Coincidence? I think not.
Rin will go back to being his happy self
By the end of the series, once everything has been resolved, Rin will revert back to his warm ,cheery personality. He has been shown smiling in a couple of official magazine pictures as well as appearing quite happy in the ED.
The five guys are genderbends of the girls from K-On
Haruka is Mio, Makoto is Yui, Nagisa is Mugi, Rin is Ritsu and Rei is Azusa.
Something's going to happen that will directly reference the light novel, thus leading to a childhood flashback.
It's still unknown how much continuity the anime and the light novel share, especially since the anime has a different version of how Rin met the group and such. But from what's been seen so far in both the anime and the light novel, at least something will match up, and we'll get a flashback based on the light novel. This Troper's guess? She think we might get a reference to Haru's near death drowning incident from chapter 2.
- It's Rei who has the near-drowning incident, but in episode 12 when Rin and his friends finally reconcile, Nagisa happily calls him "Rin Rin", his nickname from the novel.
The season or series as a whole will end with Rin winning against Haru, but it will be implied that Haru still threw the race.
Rin and Gou are twins
- Rin was born first, then Gou shortly after.
- That doesn't really add up since Rin is a second year and Gou a first year.
- But maybe Gou missed too many classes one year (due to illness, or some other reason) and had to retake her first year whilst Rin went ahead.
- Unlikely since she isn't an Ill Girl like at all
- She spent six months in a correctional facility!!!
Rin's father knew the fisherman Makoto befriended.
- Or for extra drama, they were related.
- Or for even more drama, they are the same person.
- In any case, it's likely they died in the same storm.
Haruka is from the same planet as Haru and Coco from Tsuritama
- It's a popular name on their planet, evidently.
Harukas trouble relating to people is more than a mere quirk or shyness.
- Most of his relationships revolve around water; telling him you want to swim with him means friendship, a "Without you it's meaningless" equals a love confession, Rin telling him he will never again swim against him has the same effect on him as getting dumped has on other people. ... and this is not only how it is presented to us. Considering Haruka's reaction to each of these it's clear that he perceives these the same the audience does. We never see him interacting with people outside the swim club or anyone swimming-related. Since I am not familiar with the symptoms of Aspergers or the graduations of Aspergers and other conditions I am shy to yell "HARU HAS ASPERGERS!" ... but I surely am wondering what the producers had in mind with him.
- Also notice how his behaviour got much less erratic (stripping down and trying to swim in a fish tank f. e.) when the club actually started, he could swim in a pool (that he got more friends than just Makoto who accepted his quirks might have helped too, but again, I'm not familiar with Aspergers, so I'm just shooting in the dark here.)
- I would hesitate to call Haruka 'shy'. He definitely is not. Haruka just seems extremely introverted, which has lead to a lack of social experience and low ability to relate to people. Letting Makoto speak for him probably hasn't helped him either.
- As a person who has both majored in psychology and has Aspergers myself, I would say it is extremely likely that Haru as Aspergers at very least. His swimming and water obession is most likely sensory related, and he seems to take certain things one would not think much of very seriously. Then again, it all depends. I could go in depth, but I don't want to make assumptions, as some people have criteria of one condition, that could easily fill out another. Hard to tell without a real test.
Nagisa is secretly a crime lord.
- The 'Nagisa does drugs' meme, anyone? And then there's the version of him from 50% Off...
Nitori is secretly Easta Dave.