'''WARNING: As is common with the Infinity series, a lot of these tropes are by their merely being listed next to characters here, spoileriffic. The worst cases are in a special Spoiler Characters folder that leaves all spoilers within it unmarked, but a lot of others still have major spoilers that are marked next to trope names that aren't. You have been warned.'''

! Fuyukawa Kokoro
-> ''"If there's a logical explanation for something, then I'll believe it, but if there isn't one, I... will choose the most romantic option."''

->Voiced by: Creator/RikaMorinaga

A 20-year old woman who studies psychology, more specifically mental illnesses. She wanted to travel to SPHIA to study Inubuchi Keiko, but after the plane crash stranded her in the mountain cabin, [[TheHeart she is more concerned]] [[BadEnd about keeping the other survivors alive]]. She frequently swaps bodies with Satoru, and as a direct consequence has to deal with his problems at SPHIA too.
* DrivenToSuicide: [[spoiler:In one Bad Ending, where she feels she's responsible for Yuni and Yomogi's deaths.]]
* FreakyFridayFlip: With Satoru [[spoiler:and the male twin]].
* MeaningfulName: Kokoro means "heart" in Japanese. And indeed she fits TheHeart archetype.
* MistakenForGay: For a brief moment, Satoru contemplates whether she has "other tastes".
* RedOniBlueOni: Red to Satoru's Blue.
* TheSouthpaw

! Yukidoh Satoru
-> ''"What's important isn't the result but the process. Just like it is with life."''

->Voiced by: Creator/TakehitoKoyasu

A 21-year old amnesiac who might have been an employee at SPHIA. He doesn't really remember due to being shoved down the clock tower and losing all but a few key memories, and ever since he's trying to find out who is the one attempting to take his life.

He swaps bodies with Kokoro at irregular intervals, and has therefore also to deal with the situation in the mountain cabin, [[spoiler:as well as his ex-girlfriend Lin, who refuses to accept the fact that (s)he is Satoru]].

[[spoiler:He is the ManBehindTheMan of the entire game, and his body is actually [[FreakyFridayFlip Enomoto's]]. It is also assumed that his mind is, in fact, not Satoru's (''I''), but "Self", (I, the player), [[PlayingThePLayer and therefore only remembers those facts that the player learned about him from Kokoro's route]]]].

* AscendToAHigherPlaneOfExistence: [[spoiler:One theory states that the original Satoru, I, became one with "Self" at the beginning of the game, after he fell off the clock tower.]]
* DeadpanSnarker
* EnmityWithAnObject: Wristwatches. Particularly Kokoro's. He notes that he finds pocketwatches to be more gentlemanly and considers the weight of a wristwatch to be oppressive. Every single time he's in Kokoro's body, he takes it off and places it somewhere else (Usually somewhere it wouldn't be expected to be). Kokoro actually becomes convinced that he's intentionally trying to make it hard for her to find it, but there's really only evidence of that in Satoru's route the final time Satoru hides it.
* FreakyFridayFlip: With Kokoro [[spoiler:and the male twin]].
* LaserGuidedAmnesia: Though he tends to remember a bit more than most examples.
** To elaborate: [[spoiler:He only remembers the facts that Kokoro knows from her route -- for example, he remembers his break-up with Lin, but not their relationship.]]
* MadScientist: [[spoiler:His past, true self had traits of this.]]
* TheManBehindTheMan: [[spoiler:The one behind Enomoto and Yuni.]]
* MemoryGambit: [[spoiler:It turns out his past self, ''I'', is the true mastermind behind the events of the game, and took his memories with him while implanting a few in the new Satoru's mind.]]
* MoralityPet: To Lin.
* RedOniBlueOni: Blue to Kokoro's Red.
* TalkingToHimself: [[spoiler:Happens ''literally'' in Bad Ending #28.]]
* TheSmartGuy
* TomatoInTheMirror: [[spoiler:It turns out that the body he's inhabiting is actually Enomoto's. The Infinity Series Timeline explains that the two of them switched bodies via quantum teleportation in July 2011, but the reason is never given.]]

! Kusuda Yuni
-> ''"I like prime numbers, because they have two factors. Not one, not three... but two..."''

->Voiced by: Creator/JunkoMinagawa

An 11-year old boy whom Kokoro met on the plane, and one of the survivors of the crash. Curiously enough, there's two of him: one in the mountain cabin (who continuously makes cryptic remarks about their situation), and one in SPHIA (a scared boy who nevertheless becomes friends with Hotori).

[[spoiler:The one in SPHIA is the one who recently experienced the plane crash, while the one in the cabin is from 2012, a year in the future who used the exchange mechanism to ensure the continued survival of Kokoro and the others]].
* CheerfulChild: Most of the time.
** CreepyChild: He has his moments.
* InfantImmortality: [[spoiler:Yuni's obviously not an infant, but he usually survives all the bad endings that result in Kokoro or Satoru being killed. There are only three exceptions: in one bad ending, Yomogi descends into madness and after Yuni doesn't listen to one of his commands, he grabs Yuni by the throat and breaks his neck. In another bad ending, he freezes to death and Kokoro is so filled with remorse that she lays down in the snow and intentionally dies of exposure. And in another, he dies of hypothermia and she slits her throat as an act of atonement.]]
* MissingMom: Late in Satoru's route, he says that his mother is no longer around, so he considers Utsumi to be a mother figure.
* ObfuscatingStupidity: [[spoiler:The Yuni at the cabin is from the future, and already knows everything that's going to happen.]]
* PrecociousCrush: A couple of different times, he tries to flirt with Kokoro. Although a lot of these are just played off as jokes, [[spoiler:during one of Kokoro's [[BadEnding Bad Endings]], he does a serious DyingDeclarationOfLove to her]].
* TimeTravel: [[spoiler:He uses the transfers to switch his 2011 and 2012 selves.]]
* TookALevelInBadass: [[spoiler:His 2011 self is a scared kid who has no clue what's going on and often lashes out at Kokoro/Satoru. In between the 2011 and 2012 incident, he joins up with Satoru and Enomoto, and after learning everything there is to know about the incident, he matures greatly.]]
* ZenSurvivor: [[spoiler:His real '12 self shows traits of this. He's annoyingly reserved with what he reveals to Satoru, but that's partly justified by the fact that Satoru being the one behind everything all along]].

! Mayuzumi Lin
-> ''"Isn't a person's heart something that easily changes? No flame keeps burning forever."''

->Voiced by: Creator/MegumiToyoguchi

A 23-year old rich woman who survived the plane crash, [[spoiler:as well as Satoru's former girlfriend]]. Is a court-appointed lawyer who occasionally quotes parts of the Japanese constitution to support her self-centered opinions.
* ArrangedMarriage: Has been set up for one by her family, [[spoiler:which is the reason she had to break up with Satoru. There's a blink-and-you'll-miss-it scene where she reveals that she blames herself for this; she thinks that she took the "easy way out" by not going against her parents.]]
* AssholeVictim: [[spoiler:In BadEnd #8.]]
* AxCrazy: [[spoiler:In three different {{Bad End}}s.]]
** AnAxeToGrind: [[spoiler:Yes, ''literally'']].
* IceQueen: Suiting her archetype as the "Persona," Lin puts up a front to everyone of being harsh and hyper-critical of everyone and everything. Due to the nature of the plot and her reaction to it - trying to throw everyone else under the bus in order to make sure that she survives - there are only a few moments where the facade falls and her more gentle and fragile traits show.
* {{Jerkass}}
* TheLoad: Half of the problems that the survivors of the HAL18 crash have to deal with are instigated by Mayuzumi, and most of the other half are exacerbated by her. There is only one ending where [[spoiler:the rest of the party tries to get rid of her]], though, and it's not a good ending.
* RescueSex: When Kokoro calls her out on being ungrateful towards Yomogi, she snidely remarks that she ''is'' grateful, and that she'll show her gratitude by letting him have sex with her ''once'' if they get out of the whole ordeal in one piece.
* RichBitch
* TheScrappy: Both in-universe and out. The only one who doesn't treat her like this is Satoru.
** [[spoiler: In one of the bad endings, she reveals that she acts like this ''intentionally''. Why? Well, generally she really is a bitch, but her behavior in the cabin ''specifically'' (arguing over/hoarding rations, refusing to work together with the other survivors, etc.) is because apparently she told herself that she was willing to do anything it takes to survive long enough to see Satoru again, including metaphorically throwing everyone else under the bus, and everyone else can think badly of her if they want as long as she survives this ordeal and reunites with Satoru. So she's a rare ''deliberate'' Scrappy.]]
* {{Tsundere}}: Dere to Satoru, tsun to everyone else in the world.

! Yomogi Seiji
-> ''"If there is meaning to human life, then there must be some sort of meaning to death as well. That's what I'd like to think."''

->Voiced by: Creator/MasashiEbara

A 35-year old mountaineer and one of the survivors of the plane crash. It's through his expertise that the others could survive on the mountain. [[spoiler:He's also Utsumi's husband and the father of one of the kids that Keiko murdered]].
* AxCrazy: [[spoiler:His breakdown and behavior in BadEnd #8 is truly terrifying.]]
* ItsAllMyFault: [[spoiler:Blames himself for his son Junichi's death, both for buying the bicycle that got him sent to the Awazumi hospital and for not staying the night with Junichi.]]
* MadnessMantra: [[spoiler:"I won't let anyone die any more." in Bad Ending #8.]]
* ReasonableAuthorityFigure: Given the circumstances, he's remarkably understanding of Kokoro's strange behavior that she writes off as a "split personality." Also, he's very knowledgeable about what to do to survive in the cabin, is a huge moderating influence on Lin's bitchiness, and provides stability to the much younger Kokoro and Yuni. [[spoiler: The only exception is in Bad Ending #8, where he snaps and goes crazy, deliberately letting Lin freeze to death in the basement, breaking Yuni's neck, and behaving very creepily to Kokoro.]]
* SadisticChoice: [[DiscussedTrope Discussed]] hypothetically. In one scene, Kokoro asks him which situation he'd prefer to be in: his current situation, where he's trapped in a freezing cabin on a mountain and is running out of food and water, but he's guaranteed to survive at least long enough for the food and water to run out completely...or a situation where he has plenty of food and water and it's warm but a crazed murderer is after him. Yomogi surprises Kokoro by answering that he'd rather have the murderer. Why? Yomogi's reasoning is that as long as he's not too hungry or thirsty or cold to think clearly, he could theoretically change the situation by dealing with the murderer somehow, but he can't significantly alter the situation he's actually in.
* TeamDad

! Utsumi Kali
-> ''"It's alright... no matter what happens, I'll definitely protect you."''
->Voiced by: Creator/AyaHisakawa

A 27-year old woman who works as a therapist in SPHIA. She's responsible for the well-being of the people there [[spoiler:except when she's not. She's Yogomi's wife and the mother of one of Keiko's victims and came to SPHIA [[{{Yandere}} to avenge her son]]]].
* ButNotTooForeign: Half-Indian, half-Japanese.
* DarkSkinnedBlonde: Her hair is white though.
* ItsPersonal: [[spoiler:Came to SPHIA to kill Keiko in revenge for her son's death.]]
* MurderSuicide: [[spoiler:In both of the {{Bad End}}s following her succeeding in her plan to kill Keiko.]]
* RescueRomance: [[spoiler:Her relationship with Yomogi is the result of this, as he saved her life when he found her on a trip to Nepal.]]
* RoaringRampageOfRevenge[=/=]UnstoppableRage: [[spoiler:She flips and tries to kill Hotori towards the end of Satoru's route. In an associated BadEnd, she kills both Satoru, Hotori, and [[MurderSuicide herself]] (and Kokoro, indirectly).]]
* StepfordSmiler: Outwardly a very considerate and motherly character. [[spoiler:Secretly stewing with a desire for vengeance against the woman who killed her son]].
* TeamMom
* TeenPregnancy: [[spoiler:She gave birth to Junichi when she was ''14''. The [[AudioAdaptation Drama CD]] makes it clear, however, that this was an accident, and Yomogi immediately took responsibility.]]
* YamatoNadeshiko: [[spoiler: Her plan is to kill Keiko in revenge for her dead son.]]

! Suzukage Hotori[=/=]Inubushi Keiko
-> ''"...."''

->Voiced by: Akane Tomonaga

A 19-year old girl who has killed 12 people in a hospital in 2009. She has been disagnosed with [[SplitPersonality Dissociative Identity Disorder]], so she got acquitted and sent to SPHIA for treatment. Her personality has since then more or less settled on that of Hotori Suzukage, a [[ShrinkingViolet shy]], [[TheVoiceless mute]], and generally harmless girl who befriends Yuni.

[[spoiler:Her personality is still that of the murderous Keiko, but pretends to be Hotori when she's controlling the body. She undergoes the same [[FreakyFridayFlip body-swap]] that Kokoro and Satoru do, but with the dead body of the ''real'' Hotori. Since both transfers are parallel to each other, Kokoro and Satoru only meet one of them respectively.]].
* AbusiveParents: Speculated to be the cause behind her DID, though it's never confirmed.
* AxCrazy: One of her personalities, which is the one that caused the Awazumi Massacre.
* CheerfulChild[=/=]CreepyChild: She [[MoodSwinger jumps]] between both.
* FreakyFridayFlip: [[spoiler:With Hotori and the female twin.]]
* KnifeNut
* ProperTightsWithASkirt: Sports this look pretty much all the time
* SplitPersonality: Is said to have 11 separate personalities.
** MoodSwinger: May also be this, via...
** SplitPersonalityMerge: Speculated to go through one shortly before the game's beginning, as she doesn't as much change personalities as [[MoodSwinger changes moods]].
* TheVoiceless: [[spoiler:In Kokoro's route only.]]


[[folder:Spoiler Characters (unmarked spoilers)]]

! Enomoto Naoya
->Voiced by: Shunsaku Nishigaki

A mysterious man hiding in the control room beneath SPHIA, and the one helping Satoru in advancing his plan. He is also the one inhabiting Satoru's real body, and vice-versa.

Once Satoru finds the secret room, Enomoto explains the details of the body-swap mechanism ([[MindScrew which actually isn't]]), and attempts to kill Satoru after he flips out as a consequence. He is shortly thereafter murdered by the male twin in Satoru's (actually Enomoto's) body.

* AxCrazy: Both of the times that he tries to kill Satoru (in SPHIA and in Apoptosis), he seems to relish the idea ''way'' too much for it to be considered just part of the job for him.
* ContinuityNod: He is working for [[VisualNovel/{{Ever17}} Leiblich Pharmaceuticals]].
* HoYay: With Satoru.
* TheManBehindTheCurtain
* MrExposition: He literally shows up out of nowhere in Satoru's route to explain how the transfer phenomenon works, then is killed off almost immediately afterwards by the twins.
* OneSceneWonder: Only shows up alive in a grand total of two scenes in the game (one of them being in a Bad Ending), but his scenes are amongst the most memorable.
* SmugSnake: Treats Satoru with a very condescending attitude, but when it comes down to it, he was merely "original" Satoru's pawn.
* TomatoInTheMirror: The body he's in is actually Satoru's, and vice-versa.
* VillainousBreakdown: Flies into rage when Satoru attempts to destroy the quantum teleportation equipment.

! Suzukage Hotori
->Voiced by: Akane Tomonaga

A 19-year old girl and temporary survivor of the plane crash. Shortly before her body freezes to death, she [[FreakyFridayFlip swaps bodies]] with Keiko, and is thereafter the "Hotori" whom Kokoro meets. She lost the ability to speak as a result of the trauma.

* DeathByOriginStory: Sort of. She stays alive for a while in Keiko's (and the female fetus') body, but in the end she's dead for good.
* AFateWorseThanDeath: It's implied that she didn't die immediately in the snowstorm. She was still conscious during the week.
* FreakyFridayFlip: With Keiko and the female twin.
* TheGhost: She is never seen, except for one scene in each route.
* HeroicBSOD: Briefly, after finding herself with a bloody knife over Enomoto's body.
* ShrinkingViolet: According to the [[AllThereInTheManual TIPS]].
* TheVoiceless: Caused by living through the plane crash. She apparently [[{{Subverted}} gets better]] by the end of the game, but [[DoubleSubverted loses speech again]] after surviving the avalanche.
* TomatoInTheMirror: Breaks down upon seeing her reflection (in Keiko's body), but is unable to express her situation to the rest of SPHIA due to the trauma of the crash.
* WhatCouldHaveBeen: An entire sprite sheet for her is in the game's data, suggesting that perhaps she was to play a more important role in the game proper.

! Yukidoh Sayaka
->Voiced by: Akane Tomonaga

Satoru's sister who is only seen once (twice?), at the beginning of the respective routes.

* AllThereInTheManual: Practically everything known about her is only taken from the TIPS, Infinity Series Timeline, and speculation.
* AscendToAHigherPlaneOfExistence: Possibly.
* CreepyChild
* DeathByOriginStory
* OneSceneWonder: She only appears for about a minute in the actual game.
* PosthumousCharacter
* SelfMadeOrphan: One of her personalities murdered her parents.
* SplitPersonality: It's implied that the second personality is Keiko.
** SplitPersonalityTakeover: It's also implied that Keiko did this to her.
* WhatCouldHaveBeen: A lot of unused sprites for her are found in the game's data, also indicating that she was to appear more often.

! Yomogi twins

Yomogi's and Utsumi's twin children, who were born between the two incidents. They are the respective third personalities in Kokoro's, Satoru's, Keiko's and Hotori's transfer phenomenons and responsible for most of the havoc wrought in both SPHIA and the cabin.

* AmbiguousInnocence: While their actions are very questionable, they literally know nothing, and therefore aren't aware of what they're doing is wrong.
* FetusTerrible: {{Subverted}} too. As mentioned before, they aren't aware of what they're doing or that it's wrong, and are just acting like babies would if they had adult bodies.
* FreakyFridayFlip: The male twins is the "third personality" in Kokoro and Satoru's exchanges; although only Satoru becomes aware of it very late into his route. The female twin is the same for Hotori and Keiko.
* HalfIdenticalTwins: To the point that even though Utsumi has separate photographs of them, Satoru can't tell them apart and assumes it's just one baby at first.
* InfantImmortality: Possibly subverted. The last time we see them, Inubushi is holding the girl on the edge of a cliff with a crazed look on her face. However, as [[CliffHanger we never see what happens next]], we don't know whether this is played straight or subverted.
* SpannerInTheWorks: To Enomoto.
* TheUnintelligible: While we never hear them "speak", the accounts from the others seem to indicate that when they go through their colic, they scream out unintelligibly ({{justified|Trope}}, as they don't know how to speak).

! "Self"
* AGodIsYou: Very similar to [[VisualNovel/{{Ever17}} Blickwinkel]] in this regard.
* PlayingThePlayer
* RealityWarper: When "it" sees Sayaka in Satoru's flashback and confuses her for Keiko, Sayaka [[SplitPersonalityTakeover "dies"]] and becomes Keiko. It's implied that he warped Satoru's existence and history based on what it knew about him.
* StableTimeLoop: Is caught in one, due to Satoru's plan.