Kei Karuizawa/Relationships

Kiyotaka Ayanokōji
During the survival test, when Yōsuke was chosen to watch over the boys in the class, Suzune requested Kiyotaka join him on guard duty since he needed to be watched as well. While he was picked, Kei noted on him being invisible to the rest of the class, showing that she barely acknowledged his presence in their time together as classmates.

In the light novel, much like the anime, Kei initially did not think much of Kiyotaka. She often looked down on him for being an "unremarkable guy" and appeared disgusted by his presence when they were both placed in the "Rabbit" group during the summer special test, however, she shared those same feelings with her other groupmates, Hideo and Teruhiko, so it wasn't personal.

After being saved from Manabe and her group during the cruise ship test, she starts to hold a dislike towards Kiyotaka, unable to look at him without an angry expression, and was mad when Hirata arranged a meeting with her but brought Kiyotaka with him. After being bullied by Manabe and her group in the lowest level of the ship, she was blackmailed by Kiyotaka who threatened her that he'll reveal her past to the school but assured her that he'll protect her from being bullied in exchange for aiding him on his scheme.

In volume 4, that was when their relationship starts to blossom from classmates, to platonic, and finally to mutual interest in one another. She offered him advice on how to be more proactive and popular with others. In many instances, she acted sardonically and mordaciously towards others, constantly comparing them to Hirata. Many abhor her presence and demeanor but Kiyotaka was the only one who saw past her facade of wanting to be hated and started suspecting that she might have a dark past due to her uncanny and capricious behaviour. He also recognised that she demonstrates an adequate level of maturity for not confronting Ibuki for stealing her underwear in previous volumes. Kiyotaka was depressed and felt a hint of jealousy whenever Kei got too close to others boys like Machida but knew she did it to antagonise the Class C girls, dignify herself and consolidate her power in the group, and so did nothing but observed on the sidelines. Moreover, he speculated that she attaches herself to hosts to vicariously go through school in a safe manner. Furthermore, he was impressed by the skill of her manipulation, cunningness, and strategic prowess she exhibited to get what she desired. On other occasions, he felt disgusted when he saw Kei being physically bullied by other girls and thought of ways to protect her and taking pictures of the acts clandestinely. He then sought to find out her secret by seeking Hirata. When he saw the dynamic of the fake couple, he began to understand that Kei was just afraid, helpless, and needed protection and security the most. To elevate her and allow her to grow, he started to execute his plan which was to break her down so he could personally bring her up again, forcing her to seek him for refuge. After finding Kei crying in a room, he forced her to confront her egregious past and show him her pathetic side after being bullied. He made Kei think that he was about to sexually assault her by telling her to spread her legs and grabbing her thigh which caused Kei to obey and tell him the iniquitous past she desperately tried to forget and was forced to go through. He then saw her scar, looked her straight in the eyes, and unveiled his own darkness that was reflected in them. By doing so, he eroded away her terror as those with shared darkness are attracted to one another. He promised to be more reliable to her than anyone else and gave her permission to rely on him. As proof of his words, he showed her the pictures he took to play against her enemies which would ensure her safety. Kei began to see him in a scintillating light as he was the first person to not judge her scar and embraced her weaknesses.

In volume 4.5, they are comfortable with each other's company and shared pleasantries whenever the situation allows. She starts to observe Kiyotaka in a deeper light and suspects the veracity of his showcased abilities, surprising him of her perceptiveness. He is shown to be considerate of her as he invited her to join his group and respectfully told her alternatives to hide her body scar if they went swimming. Kei decides to entrust her secret with him and lay herself bare, even though it was a vulnerable and potentially detrimental decision. There was a vestigial unease of abashment she feared he might use against her, but his next words alleviated them. He promised to destroy her enemies as long as she works with him and doesn’t bully others. They are shown to be at eased with direct body contact with one another as the real Kei usually doesn’t touch anyone else, especially boys. She was worried that she might cause trouble for him by being too close to him, allowing rumours to foster and offered to leave first. Additionally, she realised that he is willing to use dirty tactics such as expelling others so as to protect their own classmates and seems to be accepting of that fact. Just from looking into his eyes, she knew that Kiyotaka wasn’t normal and has experienced something as traumatic or even more so than herself which made them relatable. He ordered her to remove and reveal her swimsuit to which she obediently complied with signs of dissatisfaction and embarrassment. He then pushed her into the water to cool her head and get her to relax. As retaliation, once he offered his hand to grab on, she dragged him down as well, pushing his head under the water and childishly enjoying herself. Kiyotaka thought it was worthwhile letting that happen and seeing her smile again. They spend a merriment moment with one another before being chased out. Later on, she was grateful to Kiyotaka for telling her that the guys planted a spycam in their locker room and how to solve the issue.

In volume 5, she was amazed by his displayed physical abilities and praised him openly at the sports festival after he raced Manabu Horikita and nearly won. She seems to have formed a friendship with him which evolves into a close trusting bond with him, where Kiyotaka is shown to truly trust her more so than others, even more than Suzune.

In volume 6 of the light novel, it seems that she develops a crush on Kiyotaka. She immediately called him at night to ask whether Maya confessed to him and afterward if he turned her down to which she was surreptitiously glad that nothing of note happened. Kei was going on with her usual antics of being close and holding onto Hirata, but after locking eyes for a moment with Kiyotaka, she immediately detached herself. When everyone was against her when she lost her cool at a Karaoke dispute, she looked at him but was saddened to see him not on her side. In the end, she apologised and admitted that she was in the wrong after losing her cool.

Her crush on him was also hinted further in the light novels when she became jealous of Maya's flirtations with Kiyotaka. She was also the first person to celebrate his birthday, causing him to hesitate to delete her text message, which he usually does as an added precaution. He also learned of her birthday and decided to do the same for her.

In Volume 7, even though she learned from Kakeru Ryūen that Kiyotaka had betrayed her by using her from the very beginning, she still refused to betray Kiyotaka, calling him her saviour, as she refused to tell Kakeru Ryūen that Kiyotaka is the true mastermind and lynchpin of Class D, even after being threatened and abused both physically and mentally by them. She profusely shouted at Kiyotaka to run away and leave her behind when he suddenly appears, however, she was surprised to see Kiyotaka easily beating up Ryūen's gang, and angrily attack Ryūen for threatening her. She was shaken by his abilities but hugged him as she was relieved that he came to her aid as he mentioned his promise to protect her. He then comforted her and told her that if something like this ever happened again and that he would be here to protect her. By delaying his arrival and ultimately still showing up, he was able to strengthen her belief and faith in him while also ascertaining that she will never betray her. He felt horrible having to subject her to such suffering again but knew it was necessary to humble her and let her rely on him. He has successfully made her overcome her past and create a new identity for her. Their relationship exponentially improved from this point onward. as Kei felt ingratiated to him as he was the only one there for her when she needed someone the most.

Yōsuke Hirata
Since the beginning, she seems to have quickly established a relatively close and trusting relationship with Yōsuke. When the school first started, she was seen to have appreciated and supported his idea of having the students introduce themselves just before the ceremony.

After several days of school, to the eyes of schoolmates, they seemed to have form a strong bond as they are often seen together. In truth, they had just established and were just pretending to be in a relationship in order for Kei to not get bullied in school, so it is unknown how they really feel about each other.

Suzune Horikita
They don't have much interaction early on in the series and don't appear to be on good terms due to their contrasting personalities.

In episode 7, she was rather callous to her and told Yōsuke that they should leave so as to not spend more time than necessary.

During the survival test, after Yōsuke was chosen by Kei to watch over the boys in the class, Suzune stepped in. She didn't oppose Kei's request of watching the boys but requested that another boy join him on guard duty since he needed to be watched as well. After Kei mentioned that there was no other boy who seemed trustworthy, Suzune selected Kiyotaka.

In the novels, they still have limited interactions with one another but on one occasion, Kei saw Suzune and advised her to open up with Kiyotaka if she ever hopes to have a friendly relation with him. Adding on that if she continues putting him at a distance, she should then expect the same thing to happen to her. Hearing these unexpected words of wisdom from her, Suzune took them to heart and resolved herself to open up to Kiyotaka and get to know him better. Kei left soon after with her friends, being indifferent as to how Suzune would take her opinion.

Kikyō Kushida
Kei and Kikyō appears to be on good terms at least on the surface level. In episode 2, Kei went to Kikyō to borrow private points as she was out of it after blowing through her own funds and seemed desperate for points as she used their friendship as an excuse to do so however, it appears that Kikyō didn't go through with it. After Kikyo's true nature has been exposed by Kiyotaka, her opinion changed and prefer want Kikyo expelled.

Satsuki Shinohara
Satsuki is one of Kei's friends in Class 1-D. The two can often be seen interacting with each other in the anime and getting along very well.

During the survival test, Satsuki was among the many girls that comforted Kei after her underwear was stolen.

In volume 11.5, Satsuki heard that Kiyotaka rejected Maya feelings and was even more suprised that Kiyotaka said he does not like Suzune or Kikyo. Satsuki thought Kiyotaka was just a blockhead that was not intersted in love, but was surprised when Maya said she thinks Kiyotaka loves Kei and Kei loves Kiyotaka too. Satsuki was confused to why Kei would switch from Yousuke to Kiyotaka.

Maya Satō
Maya Satō is also one of Kei's close friends in Class 1-D, as they get along well. The two can often be seen interacting with each other in the anime and getting along very well.

During the survival test, Maya was among the many girls that comforted Kei after her underwear was stolen.

Chiaki Matsushita
Chiaki Matsushita is one of Kei's many friends in Class 1-D.