lowkey

In his backstory (manga-based only), we learn that he was born into a family with no love and affection. his parents never showed interest in him; they only cared about work—actually, that much—that even if they didn't love each other anymore, they pretended to be happy so the hospital where the father worked—his father was the hospital head—wouldn't get into any scandals. chishiya basically grows up in a family with no feelings, and since he never got to know them, he still doesn't know them to this day. he wanted to check if he could feel anything by starting to work in his father's hospital as a student. he wanted to know if he could feel compassion toward any of the patients and if that would help him find an interest in life; guess what, it didn’t help, then he kind of gave up on himself and looking for any sense in life or finding a good in himself

but there was one thing that interested him since he was a child: it was the Mona Lisa painting. we see him looking at it, stating that he couldn't look away and that "everyone wants to be seen for who they are"; it is a reference to his history in various ways. first, the painting, in one of its meanings, is a visual representation of happiness. looking at what he said, it could be interpreted as him referring to his family, who are actually just pretenders and are "painted" happy. the second meaning refers to him, as he always felt different from others and viewed emotional people as stupid. because of that, other people couldn't understand him; he reminded himself of the painting when he tells arisu he just wanted someone to understand him. he said the Mona Lisa, in one theory, has been said to be Da Vinci himself dressed as a woman—which refers to people actually not knowing Da Vinci, just as people do not actually know and understand him.

in Borderland, his first game was 6 of Diamonds - a blackjack. there we could see how intelligent and observant he actually is. he never gambled before and was not only able to pick up the rules through observation but also invented a mathematical card counting method to decide how to bet. other players there couldn’t understand how a young man like him could act so calm and unbothered, but he simply had no concept of living and didn't care if he died or not. from the beginning, he only "helped" others when he saw they might be useful—that's why he helped Karube and gave him information about the beach since he was with Arisu, who he became interested in.

on the beach, he paired with Kuina, but they weren’t friends, as the show depicts; he had from the beginning planned to use her to steal the cards by himself when they were about to steal them together. he needed her to get closer to Arisu—to use him for his plan—he didn't care what was going to happen to them(arisu & usagi). kuina even asked him if he really didn't feel sorry at all, but of course, he doesn’t feel anything. Kuina later in the series even said she hates him just as much as she hates niragi 10 of hearts: after the start of the game, he leaves Kuina behind and is trying to kill Niragi; he says he's pissing him off since Niragi reminds him how awful he also is. both of them don’t care about other lives, killing and betraying them. Chishiya really hated niragi. he knew there was something wrong with him, but he couldn’t change and gave it up already in his backstory. he wants niragi dead so he won’t have to face the thought of how evil he actually is. also, when he learns Arisu is alive, he doesn’t try to solve the game; he knows Arisu will do it and that he doesn’t need to interfere. especially when it’s a heart game, he may be pretty good at them, but he doesn’t really like them since he isn’t good with emotions and never really understood other people's minds.

King of diamonds: there, as usual, Chishiya couldn't care less about his life and gives Kuzuryu the option to kill him. as i said, he never had the concept of life and was only in the borderlands looking for something interesting, like, for example, his beloved Mona Lisa painting. unexpectedly, Kuzuryu decides to sacrifice himself for Chishiya, which actually makes him wonder—how do people decide to sacrifice for others? Why do they do that? He contemplates the concept of empathy. Kuzuryu's sacrifice was like a breaking point for Chishiya because, before, Arisu's will to help others interested him, but what Kuzuryu did for him made him actually think about changing.

Mira's personality may seem highly apathetic or sadistic, but her chill demeanor regarding the games and staying in borderlands stems from her desire to learn more about the human brain, human nature, and much more—it was even pointed out by kuzuryu while they played chess that he sometimes feels scared of her curiosity about everything.

in her backstory, we learn that she is a psychiatrist and neuroscientist. she was studying human brains, and borderlands provided her the opportunity to fully and naturally explore the human brain on a daily basis. that’s why she remained a citizen.

Is it possible for you to do a mira one :)

backstory: arisu grew up as a glass child. all the attention his father gave was directed toward his younger brother, hajime. he was always better at everything in their father's eyes, while arisu was seen as the stupid and failure sibling. he always compared them to each other. arisu sometimes felt like his father didn't love him; he never received attention from him. that's why, later on, he craved attention and the desire to be seen as a hero unintentionally. the hatred from his father stemmed from arisu being similar to his mother. his father considered her stupid and claimed he didn't like stupid people, which is how he viewed arisu. he even stopped taking his children to her grave, even when arisu desperately wanted to see his mom. when arisu's mother died, it was as if the only parent who cared for him had also died. his father hated him so intensely that he even made the only teacher who cared for Arisu—who encouraged him to start playing guitar—move to a different school because he wanted arisu to stop pursuing "stupid" hobbies and learn "useful" things instead.

in borderlands, he suffers significantly from survivor's guilt, major depressive disorder, which is common when experiencing such guilt and existential crisis but one by one:

7 of Hearts :: this was when his best friends died, the only people who cared for him. he was infuriated that he was the only one who survived because he believed he was a failure with nothing ahead of him. for instance, karube wanted to get married, was strong, and had a chance of surviving. he had nothing but them, which triggered his hallucinations of the people he felt he had killed in some way. because of this, he felt immense guilt; he would have preferred to die instead, but deep down, he truly wanted to live. however, he only lived for others and needed to find a reason to live that didn't involve other people.

selfishness : even when arisu seems like a character who acts for others, he mostly does it to feel better about himself, to feel as if he has done something for someone—so that now he can be viewed as the good one as the hero, to receive attention . he also acted out of pure selfishness, such as pairing usagi with niragi in osmosis because he didn't want to face the awkwardness with her after an uncomfortable moment where also he only considered what he did wrong instead of trying to understand usagi's feelings or asking her about it. that's why niragi compared him to himself and chishiya—they are all selfish. arisu never noticed this until the moment niragi hit him with reality. but when he realized it, he wanted to change right away. however, it's not so easy since he's still holding onto the past. hallucinations—it all started in the 10 of Hearts. he sees karube, chota, and shibuki and begs them for forgiveness, but his perception of karube convinces him to live for the three of them. this leads him to adopt the idea of carrying their lives on his shoulders so he would feel better about himself and what happened. the next time, during the queen of hearts, he has another hallucination. he struggles to understand his emotions and wonders if he has changed at all or if he is still selfish. he sees many versions of himself that tell him things such as: "You don't want to live, but you can't die either"; "It's easy being egotistical"; "You don't need to rely on anyone, nor trust anyone"; "Being nice to people is tiring, after all." he can't stand it; he runs away from his feelings, but then, suddenly, he finds himself in a dark tunnel, searching for an exit. he then sees chota, shibuki, and karube, but now they're giving him advice instead of blaming him, essentially telling him that his only enemy is himself. even if he thanks them, he pushes this away. then he sees kyuma, who confronts arisu, with him holding onto the past, lacking parental love and attention and tells him that's why he can't give attention to others. kyuma wants him to mature and grow up from this and tells him, "There's always an exit from the darkness. Please don't forget that." of course, it's all in his head; he knows these things already, but he uses others to help him admit it to himself. later, after hallucinating his friends dead—deaths that could probably have been easily prevented—he ends up being forced to dive into his psyche to review everything from the past, but he can't do it. (in the show, it was when arisu was shown lying in different places in the borderlands.) then usagi slits her wrists, which brings him back to reality. he truly tries to escape the hallucinations, but he meets the "old version" of himself—the one that is selfish and would not care for usagi. he then admits he hates himself, he despises who he was, and usagi's final words help him leave the hallucinations. they allow him to overcome his trauma, move forward, and find hope in usagi—hope that he can change and that he wants to do it with her, for her, and for himself.

queen of hearts: this game was arisu's deciding moment. the game was about overcoming trauma and mira's words—to have such a strong will to live that you could distinguish between what you want, what is real, and what is going on in your head. so, when he overcame it, he won the game. he finally found a reason to live and started living for himself - he wanted to change for HIMSELF - instead of others, leaving his past behind. from now on, he can fully enjoy life, and this was what he meant when he said he couldn't be like kyuma, because kyuma was never holding onto the past and fully enjoyed every moment of his life. but now, Arisu is free—free from the past and finally able to be like kyuma and enjoy his life even when his past wasn't good.

Niragi is a complicated character; he is vindictive (having a strong and/or unreasoning desire for revenge)and vengeful (seeking to harm in return from previous injury), displays sociopathic behaviour and has antisocial personality disorder.

in his backstory, we learn that he was bullied; the bullies threw balls with baseball at him, he had to eat rice mixed with their urine if he moved, and most likely, they did more humiliating things to him for no real reason. this made him wonder later in the show if they hated him because they saw how messed up he was from the start or if he became this way because of them. after the bullying, he drastically changed his appearance because he thought the only way to end the misery of his life was to change. the bullies made him believe that people like him deserved to be bullied, and because of them, he started to become sadistic, just like they were.

in Borderlands, he started as one of the martial sector members of the beach. this put him in a higher position than the usual members and allowed him to use the guns the beach offered. of course, this made him very confident, and he was consumed by the thought that he could now do whatever he wanted to whomever he wanted. most of his actions there were just sadistic and crazy things he did to enjoy his time better. however, when he saw one of the scared guys while aiming at him, niragi reminded himself of the bullying, which shows that he’s still not over it and it really triggered him.

with Usagi: on the beach, he only wanted to sa her because of his god complex at that time. in the manga, she calls him out for being pathetic and alone; in the show, she bites his tongue piercing instead, which specifically comes from the bullies who told him to pierce his own tongue. in both, she reminds him that he’s actually a loser and that he won’t change it, which makes him anxious around her since she reminds him of the bullies. when they met in Osmosis, he initially acted pretty sane, came with the idea of balance (pairing the weaker with the stronger person instead of arisu). it’s not surprising since he is the best at diamonds and is very intelligent, after all. as mentioned, he acted pretty nice for himself because of arisu, whom he felt safe around, and of course, he wanted to win that game. everyone seemed okay with him besides usagi; she was the only one who didn’t want to touch him and was disgusted by him. he couldn’t understand why she was disgusted when he was nice and actually behaved like any other person, which again reminded him of the bullying and put him in a defensive mode. for him, the only way to feel safe was to attack first, so he again tries to sa her. he even asked her, "am I really that disgusting? everyone looks at me that way"—everyone—(bullies).

after Osmosis, when he wandered around in the show, he just saw a guy on the side of the road, but in the manga, he found him in the church. there, the man tried to take his own life but failed. he lay there with a Bible by his side,niragi started reading it, and stated he was the opposite of God, since everybody loves and follows Him, while everybody hates him and hopes to not be him also made fun of the guy for trying to khs. this was, at least in my opinion, the moment when he lost all his sanity; he was comparing himself to the devil, and i think he really believed that, even though the truth is that he’s still the same person—the same “loser.” Arisu and Chishiya - after ,he finds them and begin shooting so they can all be together forever. his sanity was at its lowest, and he wanted them to experience the same madness he did—to bring them to his level. this is also why he laughed when Arisu beat him up in Osmosis; he loved to see Arisu behaving as shitty as he was. but Arisu declares that he will not shoot, bravely exposing himself from cover and talking about change, ruining his mood. then Usagi appears, and Niragi, convinced she is the reason Arisu "wants to leave him," tries to shoot her, crying and screaming that he doesn't want to be alone anymore. they were the only people he had. however, as we know, he shot Chishiya instead because of his sacrifice. then he tells Arisu that they're in a better spot because they were always viewed as normal and didn't suffer like he did - they are the majority - but if there were more "weird" people on Earth, he would be the norm, and then arisu would be seen as the devil (the weirdo) in the eyes of others instead.

with Tatta, Niragi basically hates himself, and Tatta reminds him of the "loser" side he despises. He let his anger out on Tatta and isn't genuinely happy they won because of him. as i mentioned before, he believes people like him should be bullied and are worthless, so the thought of such a loser saving his life gets him mad.