Kei Karuizawa

Kei Karuizawa is one of heroines of the You-Zitsu series as well as a student of Class 2-D of Advanced Nurturing High School. She is a prominent figure in class and is considered to be the girl's leader of Class D.

Appearance
Kei is a teenage girl of average height with waist-length blonde hair that is tied in a ponytail and purple eyes. Her school uniform consists of a light blue dress shirt below the red school blazer with rolled-up sleeves and a short white skirt. She walks in standard school shoes with light blue calf-length socks. She predominantly wears a blue ribbon around her collar. In a more casual situation, she simply wraps her school blazer around her waist and rolls up her dress shirt sleeves.

Personality
Kei is an outgoing person who spends most of her time with the girls at school and Yōsuke Hirata (her boyfriend). Typically she speaks for the girls in the class, acting as one of the leaders along with Yōsuke and eventually Suzune Horikita.

She seems to be a bit of a mooch, as after spending all her points from the first month and D-Class not receiving any, due to their penalties, she asked the girls of her class to lend her some money to buy the 'essentials', managing to gain at least 2000 points from Kikyō Kushida.

She doesn't take notice of less prominent people in the class. This was seen when she mentioned Kiyotaka Ayanokōji being "invisible" after Suzune nominated him as a guard with Yōsuke. Ironically, she befriended him in the light novels and they were very close, even being impressed by his abilities and going on a first name basis as she eventually starts to develop romantic feelings for him.

Background
Kei is a prominent figure of class. Being gifted with an attractive personality, she is considered to be the girl's leader of class D. Her development in the story is worth reading. Despite her looks and attitude she displays and the relationship between her and Hirata, she has her bunch of secrets that she cannot afford to reveal to others.

Plot
In the anime, Kei, like the other first years, listened to the speech given by Manabu Horikita, welcoming the first years to their new school. She was seen in the class talking to Satsuki Shinohara before Yōsuke Hirata asked the class to introduce themselves, agreeing with the idea.

After the teacher Sae Chabashira walked in and introduced to the class the system in which they are supposed to live in now, Kei was surprised at the fact that they received 100,000 private points, to begin with. She was seen talking with Maya Satō and Chiaki Matsushita about clothes and jewelry shopping after the classes that day. At the start of the new month of June, along with the rest of D-Class, Kei was shocked when Class D did not receive the monthly allotment of points, looking depressed throughout the explanation of S-Points and the reason D-Class didn't get any points.

At some point later, Kei went to the pool with the rest of the class, getting especially close to Yōsuke, which possibly indicates that they have been dating since. She tried asking Kikyō to lend her points along with some other girls of the class to buy herself the 'essentials', in which at least Kikyō complied with the demand. She is seen getting closer to Yōsuke, then proceeding to take the mid-test exams and passing with an overall score of 75.

During the anime pool filler episode, Kei saw Suzune walking out of the apartment building, claiming how there were rumors she had died, since no one had seen her over the summer break. Kei then left, dragging Yōsuke with her after Suzune expressed her disinterest in hanging out with the rest of her class when being questioned about it.

Later Kei, like all the other first years, took part in the school cruise, where she was seen calling Yōsuke over to hang out with her friends. When the cruise ship headed to an island, all first-year students were told they need to survive for more than a week with basic materials. Kei got into an argument with Teruhiko Yukimura about the hygienic materials they would need for survival, specifically the need for a toilet. Kanji Ike joined the argument as well, but after setting up camp, he surprised Kei, as he apologized for his words since he went through a similar event when camping as a child. Touched by this, Kei apologized for not understanding his reasons as well.

Towards the end of the survival test week, Kei was found crying in the girl's tent as her underwear was apparently stolen. The girls of her class had Yōsuke check all the boys and their luggage to find it. After minutes of searching, Yōsuke then found the underwear in Kiyotaka Ayanokōji's luggage but refrained from telling anyone, since he (rightfully) suspected that Ayanokōji was set up by someone else.

The next day, Kei and the other girls told the boys to build a separate camp from them because of the incident the day before. Kei had Yōsuke watch over the boys in the class while they moved, but Suzune requested that another boy should check over Yōsuke, since he could potentially be a threat as well. Though Kei defended her boyfriend, she agreed to the request but wondered which boy should help as all the other boys are deemed untrustworthy. Suzune then proposed that Kiyotaka be the second guard since he doesn't seem to have a lecherous side.

Kei recalled that Kiyotaka was often 'invisible' during class, admitting to herself that she barely noticed him being their classmate. In the same night, somebody had started a fire at camp by burning the survival test manual, Kei and the other girls questioned the culprit's identity, first suspecting that one of the boys must have done it. They soon, however, suspected Mio Ibuki because of she was nowhere to be found during the incident. They later learned that Suzune had dropped out of the test because of a fever. They then discussed Mio's motive and whether or not she was the actual culprit and C-Class' leader since her class had dropped out of the test earlier in the week.

The next morning, Kei was seen cleaning in the camp along with the girls. At the time of the class points announcement, she and the entire class were shocked to hear that D-Class came in the first place. Later that same day on the cruise ship, Kei and the others thanked Suzune for her brilliant plan, though, unbeknown to them that Kiyotaka actually planned everything but gave Suzune all the credit to boost her popularity in the class cementing her place as a dependable leader.

{{SpoilerSection|id=lnvol4|

Light Novel Volume 4
In the light novel, there was another exam on the ship after their return from the survival island. In this exam, their objective was to find a traitor hidden among the groups that were divided into 12 different groups based on the Chinese zodiac's names among all classes. Kei was put into the same group as Kiyotaka, Teruhiko Yukimura, Hideo Sotomura, and students from other classes such as Honami Ichinose from B-Class, Machida from A-Class, and Mio Ibuki and Shiho Manabe from C-Class. Kei couldn't hide her dissatisfaction when seeing Kiyotaka and others as her groupmates.

Kei was seen not taking part in the group discussions to expose the traitor, but she was often seen flirting with the handsome Machida from the A-Class, which eventually pissed off Manabe and her C class friends. Machida seems to taken interest in Kei due to her cuteness and he had shown a protective behavior toward Kei. Manabe and her friends then brought up the topic of how Kei shoved one of her friends, Rika, and asked for her apology. Kei then feigned ignorance and kept using Machida as a shield, which further pissed Manabe off.

After one of their group meetings, Kiyotaka and Teruhiko saw Kei getting dragged into the emergency stairs and getting confronted by Manabe and others. Manabe was still confronting Kei about the incident that happened to Rika, but Kei was being stubborn and neglected the fact that she pushed Rika. As the argument got heated up, Manabe and others lost their patience and started making physical contact with Kei. Though they began by shoving her shoulder, even this caused Kei to show strange symptoms for her, breathing raggedly and curling into a fetal position. Manabe and her friends then proceeded to grab Kei's hair and forcefully pulled Kei up, and saying that they wanted to hit Kei's face. This act of physical bullying really caused Kei to lose her previous arrogance and attitude, causing her to begin to shake and tear up to the point where the previous Karuizawa Kei seemed nothing more than a façade. Before the situation could turn even worse, Teruhiko, who couldn’t bear to watch it anymore, came to interrupt them. The situation did not get better until Kiyotaka said that he saw a teacher and said it was better for them to leave. Manabe and others left, and Kei recovered. She then brushed off Teruhiko, who showed concerns, and told him and Kiyotaka not to let anyone know about this.

Kiyotaka thought that Kei's reactions were too extreme, so he asked Hirata and learned about that Kei had been bullied since elementary school. As he learned that Kei was a capable person who could cover up her past using a new persona up until now, he decided to make her his pawn who would secretly completely obey his orders. He anonymously testified to Manabe about their issue, then used Hirata's phone to lure Kei to the ship's basement near the engine room and let Manabe's group get revenge for their friend. After Manabe's group left, he approached Kei and told her that he would save her in exchange for her obeying all orders. Kei tried to put up a strong front, but lost all will to resist when Kiyotaka glared deeply into her eye. He secretly took a video of Manabe bullying Kei at the staircase, which he used to save Kei by blackmailing Manabe's group into not approaching Kei or saying anything about Kei. Finally forming a relationship with Kei, he firstly made her go along with his plan, making A-class wrongly guess the group traitor.

Light Novel Volume 4.5
Two days before the end of summer vacation, Kiyotaka summoned Kei to a rest area where nobody was there due to the heat. He inquired about her plans for tomorrow and she answered that she was going to sleep all day because she has no more points to waste. Kiyotaka mentioned that she would receive 500.000 points next month and teasing her a little about her habit of spending points. After Kiyotaka told Kei the primary reason he called her to this place, which was to ask her a favor, Kei expressed her dissatisfaction because he didn't apologize for calling her out there first on such a hot day. He handed her a bottle of tea and she accepted it reluctantly. Kiyotaka said that he was invited to the pool by his friends on the last day of summer vacation. After muttering that she wasn't that interested in swimming, Kiyotaka asked her if she liked swimming or not, noticing that due to her circumstances, she couldn't swim openly because of the possibility that someone might see her scar. Kei answered that she's probably forgotten how to swim since she hasn't done it for years now.

While Kei was questioning what did Kiyotaka want because his holiday plan had nothing to do with her, he asked her if the school truly didn't know about her past bullying, which got her angry because this was a sensitive topic for her. After Kiyotaka insisted that this was relevant, Kei finally replied that they didn't know, and even if the school investigated the matter, they wouldn't find any evidence. But she still was grateful to the people who bullied her and to the school that covered it up, that's why she was able to grow into a new herself. Believing that Kei wasn't the kind of person who would resort to violence or intimidation in the first place, Kiyotaka forbade her to do anything that supports bullying. Kei was wondering why she felt surprisingly fine after telling Kiyotaka about her past, thinking it was odd, and then she asked if the way he's acting at that moment was his real personality, adding that at first, she believed that he's just a gloomy guy but now he was assertive and very direct. He told her to just keep her eye on him to determine what kind of person he was if she was really interested. After that Kiyotaka began to tell Kei about Yamauchi, Ike, and Sudou's plan to peep on the girls tomorrow.

On the last day of summer vacation, Kei went to the pool with her two friends and headed straight towards the locker room, finding the vent she and Kiyotaka had unfastened and replacing the memory card on the camera. When it almost closing time, Kei approached Kiyotaka who was alone, slapping his back from behind before handed him the memory card she took from the locker room. She asked Kiyotaka about his plans and if he really aimed for Class A. He answered that he was thinking about having someone expelled from the school which made Kei bewildered. She thought that Kiyotaka was awful and definitely not normal, stating that she could tell that from seeing his eyes.

While waiting until the locker room was empty, Kiyotaka suggested Kei to swim a little considering the area was deserted except for some lifeguards. Kei refused but after Kiyotaka said it was an order, she had no choice and reluctantly removed her rash guard after saying that she hated him. Suddenly Kiyotaka grabbed her arm and before she could protest, he shoved her into the pool and she shouted at him. Following her outburst, Kiyotaka offered his hand and asked if she had fun. Kei said she didn't before she pulled him into the water too without warning and laughed.

Light Novel Volume 5
At the beginning of September, only a month away from the Sports Festival, Class D began making comprehensive preparations during the homeroom period when Kiyotaka instructed Kei to object to Horikita's plan no matter what and to ask Kushida for her opinion. Though Kei agreed with Horikita's plan to pair up the stronger athletes with the weaker ones, she still conducted his order perfectly, and due to her influence in class, many have joined her side therefore in the end Hirata concluded that all of them should vote to settle this matter. After class ended, Kiyotaka exchanged looks with Kei but she went out of the classroom with two of her friends. Believing that she must not have understood his intention, he then left the classroom and getting surprised when he found that she waiting for him by the main entrance alone. Kiyotaka complimented her improvisation but not answering when Kei asked about his real intention, which angered her because it seemed like he treated her like a loyal dog. Kiyotaka then told her that there would be a traitor during the Sports Festival and said when the time comes, she would understand.

At the beginning of October during the Sports Festival, Kei had been chosen as one of the horsemen for the first-year girls' Cavalry Battle. When she noticed that Ibuki from Class 1-C led a surprise attack on Horikita, Kei gave a command to Shinohara to help Horikira's unit. But before Kei could reach Horikita, Ichinose's unit stopped them. As Kei instructed her unit to go forward, she thought to herself that it wasn't like her to do troublesome things, but for some reason, she didn't want Kiyotaka to see her suffering a defeat. Kei managed to react well to Ichinose's movement and launched a counterattack, successfully snatched a headband from her before fell off.

After first-year males Cavalry Battle, Kei called out to Kiyotaka using his first name without any honorifics, making him surprised. Kei expressed her worries for Horikita. Even though Kei didn't like Horikita because of her mighty attitude, but Kei could empathize with her due to her experience of being targeted by a bully. During the lunch break, Kei and Hirata joined Kiyotaka for lunch while discussing Ryuuen's strategy as well as the traitor. Following the race between Student Council President and Kiyotaka, Kei couldn't hide her shock from witnessing his speed against Manabu. As other students started approaching them, Kei decided to move out of the way.

Light Novel Volume 6
In mid-October, two weeks after the Sports Festival ended, Kiyotaka noticed that Kei cast a strange look in his direction before she exited the classroom. As her short, fluttering skirt caught his attention, his name was called by one of his classmates Satou Maya. Later that night, Kei called Kiyotaka while he hung out in his room and immediately asked if Satou had confessed her feelings to him. Kiyotaka wondered how did Kei know and she replied that Satou told Kei in advance that she was going to confess to him. Kiyotaka said it has nothing to do with Kei but Kei argued that she didn't want rumors floating around as well as making sure Kiyotaka wouldn't tell Satou anything about her if Satou and he started dating. Upon confirming Kiyotaka and Satou only exchanging contact information and he didn't have any feelings for her, they ended their phone call after Kiyotaka reminded Kei to erase records of their calls from the phone.

A few days later, while Kiyotaka, Horikita, Hirata, Kei, Kushida, and Sudou held a meeting at Pallet cafe regarding the upcoming Paper Shuffle Exam, in a different classroom Ryuuen was interrogating Manabe and her friends, asking why they did betray Class C. Having no other choice, Manabe explained to Ryuuen what had happened on the cruise ship, telling him the truth about everything including how they were in the same group as Kei and about Kei's past. Manabe said that she began spying because she had received threats promising to expose her and her friends for what they did.

On October 20, after chatting to his friends and speaking with Horikita by phone, Kiyotaka received a text message from Kei who was reporting her investigation regarding Shiina Hiyori, confirming that Hiyori was walking around that day asking whether people saw how much sugar Hasabe put in her coffee. Kiyotaka then told Kei that Horikita's going to contact her tomorrow but they planned to meet around 8 p.m. Kei wondering why it was so late, and Kiyotaka answered that he was busy because he was going to a movie with his study group. Kiyotaka asked Kei for another favor tomorrow and she complained. As they exchanging their goodbyes, when Kiyotaka thought that their conversation was over, he received another message from Kei. It was a cute strawberry shortcake sticker with a bunch of candles in it, not forgetting the additional message of happy birthday. Kiyotaka thought that no one would notice his birthday this year, so Kei was the first. When he deleted all the text from their conversation, he felt hesitant to delete the birthday sticker she sent. After that, he accessed Kei's profile and saw that her birthday was March 8, he decided to remember it.

At the movies the next day, Kiyotaka ran into Kei and Satou. Kei insisted that this was just a coincidence but Kiyotaka didn't buy it. After watching the movie, the group went to a karaoke bar where everyone from Class D was gathered. Following Kiyotaka's instruction, Kei accused Kushida of acting a little too nice when they were in the middle of studies and got pissed, proceeding to pour her grape juice over Kushida's blazer. Hirata asked Kei to apologize just as Kei was planning to leave. Later Kei offered to pay for Kushida's blazer to be cleaned.

On the first day of the special exam, as Kiyotaka walked into the hall on his way to the classroom, he met up with Satou who had been waiting for him. After they exchanged greetings with each other, Kei appeared and greeted Satou, before pulling Satou to go with her to get a drink before class. Hirata who watched that display mentioned that Kei was a surprisingly jealous person. Kiyotaka didn't understand so Hirata explained it further by saying that Kei had been paying more attention to Kiyotaka lately.

Light Novel Volume 7
Mid-December has passed. Following the meeting of Kiyotaka and his father, Kiyotaka resolved to put an end to all his schemes, that including cutting off his ties with Kei. He called her through the phone and asked what she was up to. She didn't believe him at all, she knew that Kiyotaka wouldn't call her without a reason. Kei began questioning why Kiyotaka was helping Class D from behind the scenes. He revealed that he had no choice but to lend Class D a hand, and then he apologized to her, saying that the reason he helped the class just disappeared and this would be the last time he contacted her. His words made her couldn't formulate a proper response and feeling confused, but Kiyotaka assured her that he would still protect her if anything happens, it was a promise. Kei didn't understand why he was saying all of this so suddenly, why did he become so cold. But he stated that it was just the extent of their relationship. Before they ended the call, Kei seemed to have something to say but didn't follow up on that.

After the closing ceremony of the second semester, Ryuuen began to execute his plan. He called Kei out to the rooftop and threaten to expose her bullying past if she didn't come. Around 2 PM, Kei finally showed up on the rooftop and demanded what Ryuuen was after. He wanted to know the identity of X, and she answered she had nothing to say. Despite being threatened that he would reveal her past, Kei argued that if he exposed her past before he could draw the answer out of her, there would be no incentive for her to tell him anything and his search for X might be delayed. Realizing that Kei wouldn't budge no matter what, Ryuuen instructed Ibuki to hold Kei down and ordered Ishizaki to fill the buckets with water. When Kei realized what's about to happen to her, she tried to break out of Ibuki's hold but to no avail. Following Ryuuen's request, Ishizaki dumped water from the bucket on Kei's head, making her collapsed on the spot and trembled. As she internally reliving the bullying of her past. Ryuuen grabbed her bangs and lifted them up, claiming that she's the sort of person conditioned to receive bullying and human nature couldn't change easily. He then dumped the other bucket on her. He asked again who's the one protecting her by shutting down Manabe's group, but Kei just shaking her head and denied it over and over. Ryuuen who felt amused continued his torture, admitting to himself that he's breaking her for his own pleasure.

After they've dumped water on her four times, darkness started to rear its head. She began to blame herself, wondering why she was being bullied, questioning why she was even alive and what she did wrong as Ryuuen laughing in front of her. She was scared, the bullying she received in the past continuously replayed itself in her head without letting up. As she's recalling her past, she wondered if Kiyotaka had abandoned her. Noticing that she trusted X quite a fair bit, Ryuuen then revealed that she was deceived, telling her the truth about the shipboard exam, how X deliberately set up her bullying to acquire the evidence, that she wasn't saved but trapped. Those words causing Kei to despair.

Ryuuen told her that there's still one way to save herself, which was to tell him about X's identity and he promised that he would never get her involved again. Feeling despair and rage at being betrayed, and her heart wishing to be saved, her lips started moving while still trembling. But to Ryuuen's surprise, Kei shouted that no matter how many times he asked her, she would never tell him, she had no intention of saying it from the very beginning. Even if starting tomorrow she lost her place at this school, and even if she continued to suffer, she would never give Ryuuen the name.

Ryuuen who felt bewildered asked why she still covered for X even though she knew they were just using her. Kei answered that she also didn't understand, she just wanted to act cool until the very end. That despite being betrayed, she didn't betray him. She was broken but still proud. If she could help Kiyotaka gain the peace he desired, that's not so bad. Her life had never been interesting except when she worked with him, things got exciting and she had fun. Although she didn't understand a lot of what they did, she felt like the heroine supporting her hero from the shadows. That's why she regretted nothing. Ryuuen declared that she's the person worthy of his respect.

As Kiyotaka showed up on the rooftop, feeling shocked Kei asked why he came here. He answered that he made a promise, that he would save her should anything happen. Kiyotaka revealed himself to Ryuuen, saying that he came to take Kei back with him. When Ryuuen threatened to reveal his existence and also Kei's secret, Kei interrupted them by saying that it was fine, if they knew about Kiyotaka then they could also reveal her secret as well. She looked at Kiyotaka and he immediately averted his eyes. Ryuuen grabbed Kei's bangs and said that her role was over. Ryuuen ordered Ishizaki to give Kiyotaka a thorough beating, but as Ishizaki approached Kiyotaka, Kei's scream stopped him. She tried to get back up and jump onto Ryuuen. But Kiyotaka assured her that she didn't have to worry as he caught the fist Ishizaki swung at him. As Kei watched Kiyotaka defeating Ryuuen and others, she was left unable to speak a word.

After the fight ended, Kiyotaka approached Kei and extended his hand, asking why she didn't sell him out to Ryuuen. Kei answered that it was for her own sake while trembling before collapsing into his chest. She admitted that she was scared. Kiyotaka told her that there's no need to think about anything right now, as of this moment, she managed to create the present by overcoming her past. He confessed that he was the one who hurt her and wouldn't ask to forgive him, but he just wanted Kei to remember that if something like that happened again, he would definitely save her.}}

Abilities
Kei was assessed as being subpar by the school whose absences and grades in middle school were direct reasons for her being placed in D-Class. She doesn't like academics nor sports, but she is surprisingly able to compete with others and

According to both Kiyotaka Ayanokōji and Kakeru Ryūen, Kei has immense mental strength.

Quotes

 * (Monologue) "The arrow of love I had let loose. If it hits, it's a magical arrow that will cause one to fall in love. This one arrow, one way or another I'll make sure to hit Kiyotaka with it."
 * (Monologue) "Jeez ... inside my heart, there was another me who was squealing while running around. There's no more mistaking it. I just have to admit it now. Seriously, seriously, seriously, my heart's seriously been stolen away. The arrow which had pierced my heart. The arrow of love which I could no longer take out. Is this even possible? Is it even fine for me to fall in love with someone who's been partly bullying me? But it's already too late. The power of this arrow is tremendous. I have, I have towards Kiyotaka-really, seriously, I've fallen in love with him.

Etymology

 * The name Kei means "favor, benefit" (恵).
 * Kei's surname Karuizawa means "light" (軽) (karu), "well, mine shaft, pit" (井) (i) and "marsh" (沢) (sawa/zawa).

Trivia

 * As D-Class is for those with defective traits, Kei's defect is her low grades and for previous absences during middle school.
 * Kei ranks #8 in the "Female Character" category in the 2019 edition of 's  guidebook.
 * In the 2020 and 2021 edition, she is ranked #1.


 * For the 2nd Year arc, When asked about her aspirations for the next year, she answered  'To spend as much time as possible with the person I love. And... to become even just a bit more useful to him. That sorta thing?'