Kei Karuizawa

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 above the usual norm.

Personality
At the start of the series, Kei comes across as a sloppy and spoiled girl who only cares about herself. She spends most of her time with the girls after school and uses her points to buy clothes and accessories. She is admired and feared throughout the class for her strong personality and her status as Yōsuke Hirata's girlfriend after only two weeks of entering the school, therefore establishing her position as the girl's leader of Class D. However, despite her looks and attitude she displays, she has her fair share of secrets that she cannot afford to reveal to others.

Behind her pompous mask that she wears in front of people, Kei is a girl tormented by the ghosts of her past who can be weak and sensitive towards her surroundings. Even though her facade is often seen as a careless, arrogant, and messy person, Kei's true self is very logical with a sharp mind, able to read the environment and the people around her, and makes the correct decision often. She is a self-aware person who knows better than anyone her own character and limitations. She also seems to have developed a cynical view of her surroundings and relationships. She believes everyone hates her and only took an interest in her due to the position and status she has in the class, making her very wary about her actions towards her friends.

When interacting with someone she trusts, Kei is a straightforward and outspoken person. This is seen in her interactions with Kiyotaka Ayanokōji, as she has expressed many dissatisfactions with him during their time working together. She also often calls out his lack of common sense regarding ordinary matters many times during the series, being the only person to actually try to fix his bad habits.

In a school that is anything but ordinary, Kei tries to live in the most ordinary way possible and spends most of her time having fun with her friends. She is very connected to fashion and fancy things, which contributes to her having an extravagant lifestyle causing her to spend money irresponsibly. So far, she’s not shown much interest in academics or a great desire to reach Class A. She often leaves to study for exams at the last minute and is not fond of studying in general. Her dislike for studying is mainly due to the lack of chances she had to attend her classes consistently during middle school due to her past. Kei entered the high school without much of the theoretical grade of middle school, which made her experience studying in high school not very pleasant.

Background
Back during middle school, Kei, who was always the headstrong, competitive type, ended up making enemies out of similar girls and becoming the target of severe and cruel bullying in their hands. They scribbled on her textbooks and stole her notes. They dumped dirty water on her while she used the toilet. They punched and kicked her and filmed it so they could spread it around the class for laughs. They put thumbtacks in her shoes and animal corpses on her desk. They even once pulled her skirt down in front of the class. After swimming class, they'd hide her underwear and sometimes even her entire uniform. They also made her confess to boys she doesn’t even like. They'd make her pick up garbage that was on the ground with her mouth and eat it. At times, she was even forced to lick shoes and those were considered the less disturbing experiences she had to go through.

Kei endured humiliation, after humiliation, and even worse accumulating experiences resulting in a very deep physical scar and the destruction of her sense of self and personality, which led to her developing Post-traumatic stress disorder (PTSD). Kei ran into this school searching for salvation and acted arrogantly to make herself look big and strong, trying to act tough so that she wouldn't be bullied again.

Due to her trauma, Kei developed a very twisted mindset based purely on the urge to protect herself from any kind of abuse or intimidation, no matter what kind of method she needed to use or the sacrifices she needed to make. The best example of this is when Ayanokouji Kiyotaka confronted her about her past and tried to blackmail her. She went as far as to offer up her body as per his request to protect her secret and place in the school. She revealed that it wasn't the first time someone had used force against her. She could cry, scream, or thrash around, but it didn't matter. She was everyone's victim, which caused her to become cold and robotic. But even though she had suffered so much, she was ready to fight again and wouldn’t give up without one.

In order to survive in this school, Kei tends to cling to someone who is valued highly and use that person's status and position to enhance her own. Due to this method, she has deemed herself as a parasite, a weak creature that can't survive on its own. Due to the fake persona she’s built up, many naive girls tends to seek her for advice on topics such as romance. However, she never held hands once with another guy but she was skilful enough to hoodwink them through her made up lies and fictitious stories.

Abilities
Kei was assessed as being subpar by the school standard. Her frequent unexplained absences and below average 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 in both when she is willing to exert effort. Kiyotaka deduced that if she worked hard for a short period of time, she would easily be able to attain significant improvements like Ken Sudō.

According to both Kiyotaka Ayanokōji and Kakeru Ryūen, Kei has immense mental strength and an indomitable will to never succumbing to the challenges of life. She has displayed the highest level of loyalty at the most crucial of moments when everything seems to hurt her which surprised Kiyotaka. Any normal person would have given up on life after experiencing just a fraction of what she’s been through, however, she has went against all odds and found true happiness in Kiyotaka. She is stalwart and will be herculean whenever Kiyotaka request her assistances, even surprising herself sometimes at the extend she is willing to go for him. She was shown to not remain crestfallen for a long period of time despite all her seemingly insurmountable difficulties for others, but if Kiyotaka ever betrays her, in his opinion, it may be her last and final breaking point.

Quotes

 * (Monologue) God is cruel. My life was destroyed because of that nightmarish day. I lost my youth, my friends, and even myself. I have to fix that mistake. No matter how much people hate me, it'll be better than suffering like that again. The most important thing is protecting myself.


 * (To Kiyotaka) "Well, whatever. It's not like this is the first time someone's used force against me. After a while, I gave up trying to resist. That's right; I was everyone's victim. I became cold, robotic. I could cry, scream, or thrash around, but it didn't matter. So, why aren't you laughing? Why don't you laugh at the pitiful loser who's been bullied all her life?"


 * (To Kiyotaka) "I'm grateful to the people who bullied me, and the school that covered it up, No one here knows about my past. That's why I was able to become a new me."


 * (To Kiyotaka) “It’s just... I don’t really like bringing up my past. I thought I’d never tell anyone about it. But I ended up telling you, and it felt so surprisingly fine that it’s kind of odd..."

Name Etymology

 * The name Kei consists of kanji that mean "favor, benefit" (恵) (kei).
 * Kei's surname Karuizawa consists of kanjis that mean "light" (軽) (karu), "well, mine shaft, pit" (井) (i) and "marsh" (沢) (sawa/zawa).

Trivia

 * As D-Class is for students with defective traits, Kei's defect is her low grades and for frequent unexplained 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?'