http://tvtropes.org/pmwiki/pmwiki.php/WMG/MyYouthRomanticComedyIsWrongAsIExpected
Please add new theories at the bottom of the page.
Hayato took the bullies' side and caused Yukino's individuality
It's been hinted several times that Hayato made a mistake in the past which cost him the friendship he had with Yukino. As Yukino explained it herself, the cause of it was jealousy. She was too perfect for the other girls and these tried to made things fair by making her life harder every day. But Hayato never helped her and decided to abandon her instead since taking her side would have ruined his social image which is the thing he cares for the most, even more than Yukino. This forced Yukino into never rely on someone again as her trust with Hayato have been destroyed and took everything on her own hands while growing to hate Hayato for chosing superficial relationships over her.
- Semi-Jossed, as it's strongly implied that Yukino initially said that she didn't want his help or would be fine on her own, so Hayato didn't get involved, possibly both taking Yukino's word and hoping that things would resolve themselves. When she kept getting bullied, Hayato attempted to step in but failed, potentially making it worse. While Hayato didn't side with the bullies, the two were nonetheless estranged, leading to Yukino as we see her at the start of the series. The event, though discussed somewhat vaguely, is brought up in direct contrast with Hachiman's actions during the prom arc, when he does what a younger Hayato couldn't and resolves to help Yukino, no matter what, even if she claims that she doesn't want his aid. Note that when Hayato indirectly apologizes after the marathon for his childhood failure, Yukino accepts and thanks him for trying, which she wouldn't have done if Hayato had outright taken the bullies' side.
Hayato is/was Yukino's crush
Possibly way off the water, and possibly reached Pluto on this WMG. But the series does seem to imply this.1a) The Hayama family and the Yukinoshita family are very close to one another, and Hayato and Yukino are both in the same grade. Perhaps they wanted an arranged marriage between the two?1b) Alternatively, the families wanted Hayato to marry Haruno, as Haruno is the eldest child of the Yukinoshita family and is the more preferred child, causing Yukino to yearn to escape her sister's shadow by being the best at everything.2) Hayato is jealous of Hikigaya for being able to achieve his goals, as Hayato does not want to seem to prefer one side than another.3) Yukinoshita aims to improve everyone, rather than to let everyone undermine her. This causes her to be at ends with people like Hikigaya and Hayato, who tend to remain static after solving problems.4) Combined with WMG stated above - At one point, Hayato showed his true side to Yukino, but betrayed her when he took the bully's side. Why the two of them still know each other is through family relations.
Therefore, I conclude with this. Yukinoshita tends to grow more warmer with Hachiman not because of who he is, but because of who he reminds her of. Hikigaya has not a mask to hide behind unlike Hayato. However, Yukino does not want to reveal her feelings to him in case she gets hurt again, but will reveal her feelings in the end of the series, as she knows that Hikigaya will not betray her.
He never does fully explain why he was ridiculed by his classmates through all of his elementary and middle-school years. His only excuse is that he is seen as 'gross' by others, but there is nothing to back-upon his claim.
Jossed. His interactions with Kaori during the double date are evidence of his claims.
Origins of Hikigaya's nickname Froggy-kun
Throughout elementary and middle school, Hikigaya has been ostracized by his classmates for simply being 'weird'. Although not much of Hikigaya's life during elementary and middle school is revealed to us, the audience, we can deduce or WMG his situation with the facts given.
1) His parents are not always home.2) He has his younger sister to take care of.3) His classmates created an imaginary virus after him.4) The same classmates also gave him the nick-name Frog.5) Girls generally find Hikigaya to be disgusting.
I believe that Hikigaya's nickname Froggy-kun comes from an insult made by the rest of his classmates due to his constant absence from a disease from when he was younger. Perhaps in his earlier years, this sickness made him sound like a frog and he had to stay at home for long durations of time in order to recover - only going to school sparingly. However, since his parents were gone frequently, Hikigaya had to miss out on school for long durations of times in order to care for his younger sister.
Since Hikigaya did not come to class frequently, the kids started making rumors that Hikigaya was part 'frog' and that he had to leave school to find a cure to become human. Since kids are idiots, they also thought that Hikigaya's frog disease was contagious and nobody wanted to stay with the boy who transformed into part-frog and wanted to be a frogman like Hikigaya.
- According to the light novels, it stems from a grade school field trip where he had to hold hands with a girl and was so nervous that his hands got all sweaty, with excessive sweat invoking a slimy frog, as with Zaimokuza during the judo tournament.
The girl who will eventually win Hikigaya's heart is a Totsuka.
Not his old friend Saika but Saika's identical twin sister who is just as sweet as he is. The only thing holding Hikigaya back is the fact that Totsuka is a boy. What if there is an equally attractive Totsuka who is a girl? She would sink his battleship in one shot.
Hachiman will become the new student council president in his 3rd year
The opponent he'll be running against is Yukino, who falsely assumes Hachiman won't make a good president.It ends with Hachiman winning votes from people who he helped over and their friends.Yui will be more torn during this arc, feeling she fails as a friend.
Hayato has been concerned for Yukino since their estrangement, though both Yukinoshita sisters forced him to keep his distance; still, it's obvious as early as the tennis match, when he tries to call it when Yukino's stamina runs out. It seems fair to guess that he knows about the Service Club and that Hachiman is part of it; while it might initially have been a genuine mistake, Hayato was probably a little jealous after his first visit to the Service Club; when he comments that they're friends, he makes a point of including Hachiman with Yukino and Yui. Hayato's greatest failure was his inability to be the friend that Yukino needed, and Yukino's already started opening up thanks to Yui and Hachiman, so intentionally misnaming Hachiman is a harmless bit of pettiness that even Hayato can indulge in: At most, it mildly annoys Hachiman, so it doesn't hurt anyone, and it can be passed off as an accident thanks to Tobe, so it doesn't seem out of character for Hayato's persona.
This also makes sense if you think about Hachiman and Hayato as foils: Hachiman is frequently petty but ultimately has noble ideals, so Hayato has noble ideals but can also be secretly petty. He starts addressing Hachiman properly after the incident at camp, which Hachiman notes is when they started seeing each other as actual people rather than "Hayama Hayato, the school ace" and "Hikigaya Hachiman, the school outcast," making it a sign of respect on Hayato's part: After seeing what Hachiman was willing to do to help Rumi, it was likely when he started to believe that Hachiman could truly help Yukino.
Hachiman's attraction to Totsuka is at least partially because he's non-threatening.
Hachiman specifically praises his cuteness, his sweetness, his soothing/calming aura, how he's so supportive of Hachiman— In other words, traditional feminine traits that are absent or downplayed in every other female Hachiman encounters. Yukino is an elegant
Aloof Dark-Haired Girl and
Defrosting Ice Queen, Yui is flashy and trendy (which, with her large breasts, spurs Hachiman to initially label her a slut), Miura is an
Alpha Bitch with blonde
Drill Hair, Ebina is a rabid
Yaoi Fangirl, and even Sensei is "old" and prone to out-of-date anime references and semi-comedic violence. Each of them has either an intimidatingly attractive appearance, a strong and potentially overpowering personality, or both, which goes against Hachiman's desire to lead a hassle-free life. Totsuka has all the stereotypical traits of a classic anime
Nice Girl, whose role would be to soothe and quietly support the male lead, while the fact that Totsuka's male means that Hachiman never has to seriously worry about a romantic relationship with him or deal with the vagaries of conversation with actual girls, who are unpredictable and who he initially shows an anxiety-induced aversion to. This probably stems from Hachiman's traumatic rejection by Orimoto, who's pretty and confident and seems to have no problems rejecting someone or actively pursuing someone she likes.
It's notable that Totsuka's role in the series, and his focus in Hachiman's thoughts, decreases as the story progresses, along with the earlier off-tangent rants that dominated Hachiman's early-season speech and monologues. This occurs as Hachiman gets to know the people around him, especially the girls, and becomes less intimidated by them; indeed, Hachiman's growing fondness for the female characters often coincides with Hachiman noticing "softer" aspects of their personality. While this doesn't stop Hachiman from noting Totsuka's cuteness, it becomes less prominent as he spends more time with the girls and finds them less-daunting, allowing him to appreciate and interact with them more and decreasing his reliance on Totsuka as a female/"heroine" substitute. It's notable that his other positive, pre-series feminine figure is Komachi, who Hachiman gushingly praises in a very similar way, and who - by virtue of being his little sister - is similarly off-limits as a romantic partner and thus, non-threatening/non-anxiety-inducing.
