Chidori: Niyama-san, what's wrong? Nico: Nico is looking for Zantoman. Chidori: Zantoman? Nico: Yeah! It's the fairy of sleep. When it throws sand at you, the sand gets into your eyes, and it's like "ow, ow, ow!" and you fall asleep, and dream, and lots of marbles fall from the sky!
Katsuhira, when he is seen acting aloof in situations where one would normally be in pain. A prominent example of this is when he literally jumps off an overpass and onto moving traffic while on a mission to prove to the seventh Kiznaiver, Hisomu Yoshiharu, that their bodies are truly connected. Upon jumping, he hits the top of a truck and bounces off of it, landing (conveniently) on the backseat of an open-roof car. He proceeds to sit up and apologize to the passengers of said car as if nothing happened, going so far as to ask about the car's welfare as Chidori and Tenga rush over to him.
Chidori: Kacchon! Katsuhira: Oh, Chidori... Chidori and Tenga:[gasps at the amount of blood on Katsuhira's face] Katsuhira:[makes a thumbs-up signal] I'm fine... I think it's just... a slight concussion... [faints] Tenga: You're not fine at all! Chidori:[faints] Tenga:[catches Chidori] You, too?!
Alternative Character Interpretation: All of the Kiznaivers have enough depth to them where their personalities can be interpreted differently. For example is Yuta a Handsome Lech or is he simply acting like one because he's Formerly Fat and enjoys the attention he's getting?
Is Maki a Jerkass who is mean just because she simply hates everybody she meets, or is she someone deeply scarred and hurt who is afraid of getting close to other people due to a Dark and Troubled Past?
Episode 7 solves this, but adds another question to her character: was she in love with Ruru, and were she not ill, would they be dating, or is Maki straight or not interested in Ruru like that?
Did Ruru manipulate Maki and try to force her feelings on her, or was she mad when she told Maki about the letter, and never really meant any of those things, correcting them with the letter on their manga's last chapter?
Ass Pull: Some people believe that Nico's crush on Tenga comes from out of left field as they seem to believe there was no foreshadowing of any kind to imply that she liked him, perhaps written in an attempt to highlight the emotional trauma of episodes 8 and 9. However, there is also the side of fans that believe Nico's feelings had been slowly and secretively built in the background since the moment Tenga complimented her in Episode 2 and was subsequently subtly hinted at in a series that is known for its constant symbolism. There is no middle point on both sides, and it's a very polarizing issue for the fandom.
Hisomu. He seems to know about the Kiznaiver system, so his antics throughout episode three come off as very selfish and conceited. His demeanor as he moves giving off the air of a child only adds insult to injury. You either think he's funny and makes the show more interesting, or you hate him for being selfish, rude, and inconsiderate to his fellow Kiznaviers.
Chidori, is she an generic character whose love for Katsuhira is stealing the spotlight from the other characters or a complex character whose love for Katsuhira makes her more compelling? After Episode 9 the fandom is split on whether she's entitled to focus on the pain of her broken heart after Katsuhira completely ignored the heartfelt confession she has been working on for so long, or if she's a selfish person that is more focused on her own romantic feelings without considering Katsuhira's wellbeing after finding out his massively tragic backstory and trauma.
Katsuhira is split between people who think he's a interesting protagonist and others who seem him as very generic at best, unlikable at worst.
Tenga fell very hard into this trope in Episode 9. On one side, there are those who think his beatdown of Katsuhira was justified. On the other side, there are those who feel like he was acting like a hypocritical Jerkass throughout the episode.
Mari Okada's involvement in the series. Given the melodramatic tone of most of her works some feel as if it's going to go down the same route as her other shows. Others however were pleasantly surprised with how the plot for the series left itself open for melodrama but Okada seems to be taking a more comedic approach to it than usual.
The series ended up having only 12 episodes, for some it was the perfect amount, not give nor take. Others wanted the anime to be longer, since Maki was the only one to gain a arc-long focus, including episodes 6 and 7, leading every other character to feel under developed, or that they developed on someone else's story. All fans though agree that they would like a prequel focused on the Original Kiznaivers.
It's left in the air whether Yuta has or not some sort of eating disorder and self-esteem issues, both due to being Formerly Fat.
Episodes 2 and 5 hint that Maki might have Post Traumatic Stress Disorder.
Ensemble Dark Horse: Hajime Tenga instantly became the most well-liked character among the cast for his over the top upbeat personality and similarities to another darkhorse.
Nico's popularity blew up similarly to Tenga's on Tumblr particularly, due to her quirky personality and overall cute/weird design. This being similar to how Mako's popularity in the Kill la Kill fandom grew.
Hisomu also had his own large group of fangirls before he even appeared in the series.
Epileptic Trees: The fans of the series spout theories about the Kiznaivers, the Kizuna System and its purposes left and right. This is understandable as the series is pretty vague about a lot of things.
Maki/Yuta started picking up steam after the events of episode 5.
Tenga/Chidori get this as well, largely due to their similarities to Kamina and Yoko. They get a nice helping of Ship Tease in the last episode, at least.
Many people jumped onto the Katsuhira/Sonozaki ship in Episode 10.
Fandom Rivalry: Some who like Space Patrol Luluco exclusively have a one-sided rivalry with fans of this series, denouncing it for its Darker and Edgier approach. It's one-sided because those who like this series also like Luluco, so it could be, at worst, a Friendly Rivalry.
Growing the Beard: Episode 9 is when the series truly started to become Darker and Edgier on an emotional scale, and episode 10 continued this trend.
Ho Yay: Between Hisomu and Katsuhira. Hisomu has an almost Yandere-esque reaction to Katsuhira deciding to help him. Not to mention, Katsuhira jumping into the street led Hisomu to an orgasm, literally meaning that Katsuhira made Hisomu climax.
Iron Woobie: Nico shows signs of this as she is completely willing to deal with her unrequited love and her pain so they can all be friends again. Even after everything in episode 9, she states how that was the best summer of her 17 years.
Tenga has been paired with Katsuhira, Yuta, Chidori, and Nico.
Les Yay: Ruru and Maki are all but stated to have a relationship. Episode 7 reveals that Ruru was really in love with Maki, but Maki rejected her feelings out of fear that she'd grieve over her even more when she died. Later it's confirmed by Urushibara that Maki still has feelings for Ruru to this day.
Red vs Blue, a term to describe the Ship-to-Ship Combat between Chidori (Red) and Noriko (Blue) over Katsuhira. Shipping in general is named after the dominant colors of the girls and their respective crush. In addition to Teams Red and Blue mentioned, there's also Team Orange is for Nico/Tenga. Often, Engineered Hashtags will be added to the name.
Sonozaki's smile in episode 10 has gone viral, usually with comments about how her beautiful smile makes her the best girl, or how it's singlehandedly converting people to Team Blue.
As a result of the series' divisive reputation among Trigger fans, the show (and its characters) has been called the "Killer(s) of Anime" among its detractors, as opposed to the usual "Savior" title Trigger characters tend to get.
To a degree, it happened to all characters who were even Base Breaking Characters: Chidori was getting hate after starting to show It's All About Me tendencies, Katsuhira was being accused of being a bland character, Tenga for being a Hypocrite in episode 9, and so on. Epsiodes 10 and 11 focus on their issues, getting over them and starting to care more for the people around them, such as Chidori finally understanding that she made Tenga go through the same pain she went, Katsuhira becoming Not So Stoic, doing a Skyward Scream after meeting the original Kiznaivers and wanting everybody to be friends again, and Tenga showing tendencies of wanting to be friends again, and wanting Chidori to properly turn him down and intending to do this to Nico, so they can all have closure.
Romantic Plot Tumor: Many viewers feel that the Ship Tease between the main cast, the love triangle between Katsuhira, Chidori and Sonozaki, and the constant Strangled by the Red String moments are consuming screentime that could focus on other things.
Ultimately, the romance becomes a important part of the plot, so it's a downplayed case.
Ship Mates: Katsuhira/Sonozaki shippers usually pair off Chidori with Tenga.
Ship Tease: Nico often holds Tenga's hands after he says nice things to her when she gets over her head afraid people will hate her.
Besides pushing him down the stairs to his near-death, Sonozaki treats Katsuhira pretty tenderly compared to the other Kiznaivers. Katsuhira is also kind toward her, doing things like exchanging email addresses, inviting her along to the summer training camp (to which she accepts), and carrying her luggage for her.
Tenga says to Chidori that she has a cute side after she accepts his offer to help her and Katsuhira get together. She then reacts in the true Tsundere fashion.
Maki and Yuta start to get this as of episode 4, including a scene in episode 5 in which they are caught with Maki trying to show Yuta her boobs.
When Tenga repeatedly compliments Chidori's food and talks about how amazing she is, there's a shot of Nico's eyes, and she's not looking too happy. Nico also seems proud of her endowment over Chidori's, which could be seen as part of her secret rivalry with her.
Tenga and his fixation on Nico's "boobies," first in Episode 2 when he jokes about fondling them, and again in Episode 8 when he catches a peek at her bra through her Sexy Soaked Shirt and gets super embarrassed, asking her to cover them up while he looks away.
Ship-to-Ship Combat: Tenga/Chidori vs. Katsuhira/Chidori. Fans are divided if Chidori deserves to have her feelings for Katsuhira reciprocated despite his inability to feel emotions or Chidori is wasting her time and Tenga is a much better and kinder friend to her.
That's not even getting into the fans who clash over Katsuhira/Chidori or Katsuhira/Sonozaki.
Many fans thought the reveal of Nico having feelings for Tenga in episode 8 was this, given that the clues for it were so subtle that one could not be blamed for not seeing them at all. Doesn't help that Nico's direct interactions with Tenga before the reveal could've been chalked up to the former's I Just Want to Have Friends attitude, while the actual romantic hints were more focused on jealousy towards a rival, Chidori, and the real Ship Tease moment came in the same episode as the reveal itself. One could only really connect the dots together when other characters pointed it out as if Everyone Can See It had been taking place all along, despite Nico's feelings being not nearly as obvious as they made them out to be.
Tenga having feelings for Chidori could be perceived as this as well, since Tenga's offer of helping Chidori out with Katsuhira didn't really seem to be anything else other than a Friendship Moment at the time. It didn't however bother the fans as much as the first example since Matchmaker Crush is often a common development, the characters had a fair share of interactions that could be interpreted as Unresolved Sexual Tension and the pairing itself already had a number of shippers, so the reveal didn't feel that it had come out of nowhere.
Take That, Scrappy!: A lot of fans were starting to get angry at Katsuhira for blatantly ignoring Chidori's feelings to go for Sonozaki, even fans that actually did like him, so when Tenga punched him for it, a portion of the people rejoiced.
They Wasted a Perfectly Good Plot: While everyone nearly universally agrees that the concept and visuals are great, many fans feel like the anime wasted too much time focusing on the romance, when the story could have been much stronger by developing the characters as individuals. This isn't helped by offhanded remarks about Tenga's parents, Yuta's eating habits, and Nico's insecurities, which all tend to feel like unfired Chekhov's Guns, especially since Maki had an entire arc focusing on her.
This is also why some fans felt as if the series should have been longer, so as to give each of the characters their own dedicated Character Development arcs (instead of solely focusing on Katsuhira and Sonozaki, with Maki thrown in), which may have resulted in the series feeling more complete and respectful to the entire cast for some viewers. A fair few fans would have actually preferred this alternate manner of approach to the Kizna Experiment instead of the actual plot. This may also be a particularly painful case of What Could Have Been, as series composer Mari Okada was rumored to have vaguely stated that the show was originally going to take quite a different course, but that she and others involved with the series decided to change it at the last minute, ending with the tone shown in the series. Considering Mari Okada's apparent artistic vision, however, this "last-minute decision" may not come as a surprise to some followers of her work.
As if to add insult to injury, Maki'sCharacter Development arc could easily be interpreted as existing solely to further the show's pre-existing endgame, which in the long run subjectively had little to do with Maki's character itself and more to do with creating a tighter dynamic between the Kiznaivers in order to immediately push that dynamic to its limits, which possibly only needed to occur In-Universe in order to cause Katsuhira to regain his memories as per Sonozaki's goal, in effect reducing Maki's story to little more than an easy avenue toward achieving that end. Overall, the fact that only Maki got a dedicated character arc out of the six newcomers to the experiment comes across as a little strange at best and incredibly jarring and suspicious at worst.
According to Crunchyroll, one of Kiznaiver's producers, the other Kiznaivers' backstories were supposedly Saved for the Sequel (in this case, the sequel being the tie-in novel), however thus far no fan translation has gone beyond the introductory prologue and no official translation whatsoever of said novel exists as proof or reference for Western audiences.
Nico, specially after episode 9: she is in the bottom of the Unrequited Love Chain, and Tenga blatantly ignores her feelings, even when she is clearly hurt right before him.
Chidori as well in episodes 8 and 9. After episodes of her getting several hints that Katsuhira is infatuated with Sonozaki and barely acknowledges Chidori's current feelings for him, in Episode 9 he unceremoniously leaves her while she's confessing her feelings to him to (literally) run after Sonozaki. Then in Episode 9 the Kiznaiver experiment puts her along with the other five protagonists in a video room to watch Katsuhira and Sonozaki's subsequent interaction in the gym, and Chidori has to listen to the boy she likes telling another girl that he constantly thinks about her, and to Sonozaki claiming that she and Katsuhira have met in the past, and so Chidori isn't even his only childhood friend anymore. It's nearly impossible to not feel for the girl when she reacts by kneeling and covering her ears due to emotional pain.
The children in the first Kizna experiment. The side effects of the project led to several of them losing all of their senses and unable to live among society. The others, like Katsuhira, weren't much better off, being almost completely devoid of emotion and unable to feel pain. Meanwhile, Sonozaki had to cope with all the pain of eighteen other children being passed onto her, and has had to suffer from that pain every day for twelve years. It's no wonder she tries to jump.
by Boom Boom Satellites.