Karuizawa Kei

Biodata

Background / History

Karuizawa entered Class 1-D already focused on maintaining a fashionable social image. While her circle planned to spend its initial point allowance on cosmetics, she joined in the broader culture of carefree spending. 3

She had previously been bullied and views weakness as dangerous. To avoid reliving that experience, she adopted a gyaru persona and became a leader among several girls in Class 1-D. 14 28

Her bullying lasted through three years of middle school and included humiliation, physical violence, and an attack with a blade that left a scar on the left side of her abdomen. She fears that exposure of her past could destroy the strong identity she has constructed at school. 57

Her spending on clothes, cosmetics, and outings helped sustain her “gyaru queen bee” image, but left her nearly penniless when Class 1-D’s monthly Private Points fell to zero. 33

Appearance

Karuizawa is a petite, well-proportioned girl known for an elaborate gyaru style and polished presentation. Her appearance is a major part of the social image she works to preserve. 14 33

• Brown-gold or golden hair, typically worn in a high ponytail. 14 28
• Often wears Class 1-D’s uniform with a burgundy blazer, light-blue shirt, bow, white pleated skirt, and light-blue knee socks. 28
• Her casual gyaru outfits include fashionable cardigans, pleated skirts, cosmetics, and carefully styled hair. 15 33
• Has a long scar beneath the ribs on the left side of her abdomen from an attack during her middle-school bullying. 57
• Gets a cherry-blossom-pink manicure and tries to draw Tatsuya’s attention to it. 56

Personality

Karuizawa projects confidence, pride, and the assertiveness expected of a gyaru clique leader. She is highly conscious of appearances, social attention, and the protection that a strong public image can provide. 14 33

Behind that facade, she is anxious about bullying, financial insecurity, and academic failure. She becomes visibly embarrassed when Tatsuya gives her affectionate attention, yet increasingly trusts him with her vulnerabilities. 28 29 30

She is also adaptable. Although initially reluctant to participate in Tatsuya’s schemes, she accepts a role in his negotiation plan and confidently argues that acting like a spoiled gyaru is simply acting like herself. 34

Her fear of being labeled broke is bound up with memories of bullying. Receiving points and being entrusted with a Class Committee role give her both practical security and a way to contribute openly. She seeks Tatsuya’s personal recognition as well as his protection, though she often disguises gratitude or affection with teasing and irritation. 37 44 57 58

Skills & Competencies

Social Image Management

Karuizawa rapidly established herself among the girls of Class 1-D through her gyaru presentation and social activity. 14 28

• Maintains a glamorous image through fashion, cosmetics, and outings. 33
• Understands the protective value of being seen as socially powerful. 14 28
• Is sensitive to rumors and classmates seeing her with Tatsuya. 30 33
• Uses her influence among the girls to endorse Tatsuya’s candidacy for class secretary, prompting members of her circle to support him. 40

Role-Playing and Negotiation

Karuizawa can use her gyaru persona deliberately when working with Tatsuya.

• Agrees to play the “bad cop” in Tatsuya’s plan to purchase old midterm papers from desperate upperclassmen. 34
• Is instructed to act willful, impatient, and unwilling to spend points in order to pressure the sellers into lowering their price. 34
• Accepts the assignment as payment in kind for renewing her rental-boyfriend arrangement. 33
• Improvises convincingly as Tatsuya’s demanding girlfriend, helping reduce the second-year sellers’ asking price from 100,000 to 10,000 Private Points. Tatsuya praises her acting and bargaining afterward. 35
• Recognizes a loophole in the dormitory rules: the after-eight restriction bars boys from the girls’ floors but does not explicitly bar girls from visiting the boys’ floors. 56

Academic Persistence

Mathematics is a major weakness for Karuizawa, especially indefinite integrals, but she continues attending tutoring sessions and begins to feel that the material is entering her head. 28 33

• Requires extensive help from Tatsuya to work through math problems. 28 30
• Worries that poor mathematics performance could lead to expulsion. 30
• Makes gradual progress when given structured tutoring and encouragement. 30 33
• Reviews differential equations with Tatsuya after receiving her share of the points he earned from Sakayanagi Arisu. 37
• Scores 74 on Horikita’s practice test and reports that the girls’ study group is likely to pass the midterms. 56
• Continues studying when the midterm exam scope expands shortly before the test, despite fearing that the change may undermine the class’s preparation. 59 60

Class Organization

As a Class Committee member, Karuizawa helps organize academic support for the girls of Class 1-D. 44 45 46

• Supports the committee’s plan for Horikita to coordinate class-wide study, with Karuizawa and Kushida overseeing the girls’ group. 45 46
• Challenges classmates who resist study sessions, arguing that past papers are of little use if they cannot understand the questions. 47
• Later opposes buying more exam questions, pointing out the cost of the earlier papers and the class’s shortage of Private Points. 71

Relationships

• Tatsuya Sakuya — Her pretend “rental boyfriend.” Kei initially pays him 10,000 points per month for protection and appearances; their arrangement develops through dates, tutoring, mutual care, and her agreement to work under his instructions when she cannot pay the renewal fee. They subsequently cooperate in negotiations and class activities. Kei increasingly values his recognition and protection, while their closeness acquires romantic undertones without ceasing to be complicated by their original arrangement. 14 15 28 33 34 35 44 56 57 60
• Maya Sato — A member of Kei’s gyaru clique who catches Tatsuya escorting Kei to her dorm room and teasingly assumes they are dating. Maya later visits Tatsuya with Kei and Matsushita Chiaki to request midterm tutoring. 30 43 44
• Kamuro Masumi — Kei becomes jealous after seeing Kamuro leave Tatsuya’s dorm with him, asserting that he should respect her position as his employer. 23
• Hirata Yousuke — His public relationship with Kei had helped protect her socially, but she came to believe his non-confrontational nature could not provide the security she wanted. They later serve together on Class 1-D’s committee. 14 45
• Kushida Kikyou — Kei invites Kushida to meet Tatsuya about the midterm papers. The two later serve on the Class Committee and share responsibility for the girls’ study group. 37 45 46
• Horikita Suzune — Kei supports the proposal that Horikita coordinate Class 1-D’s study groups and presses her to accept the responsibility. She later backs Horikita’s argument that the class should study rather than depend on more purchased questions. 46 71
• Class 1-D girls — Kei occupies a leadership position among the class’s gyaru clique and spends heavily to maintain that status. She later uses her influence to support Tatsuya’s election and helps oversee the girls’ exam preparation. 3 28 33 40 46

Story Role / Major Arcs

Rental Boyfriend Contract

After Tatsuya becomes the school’s top swimming performer, Kei approaches him privately at a Keyaki Mall café. Citing her need for protection and the benefit of being seen with him, she offers 10,000 points per month for him to pretend to be her boyfriend; he accepts after she transfers the first payment through Line. Hirata’s existing social protection has not dispelled her fear of being powerless again. 14

First Date and Growing Familiarity

Tatsuya arranges a date at Keyaki Mall, albeit arriving half an hour late. He pays for Kei’s chosen cardigan and pleated skirt, secretly buys her a heart-shaped hair accessory, and receives a jokingly low score for his performance. 15

Tutoring and Dependence

Kei turns to Tatsuya for help with mathematics. Their café sessions lead to an awkward head-pat incident, a supermarket trip, and Tatsuya cooking omurice for her while continuing to tutor her. 28 29 30

Zero-Point Crisis

When Class 1-D loses all of its Class Points, Kei is unable to renew the rental-boyfriend contract because she has spent nearly all of her savings maintaining her image. She agrees to work according to Tatsuya’s instructions in exchange for continued protection, provided he keeps his promise not to let her be expelled. 33

Midterm Resource Plan

Tatsuya recruits Kei for a good-cop/bad-cop negotiation aimed at buying old midterm papers from a Class 2-D couple. She accepts the role of the demanding girlfriend, using her gyaru persona as part of the pressure tactic. 34

Kei’s improvised complaints and threats to abandon the deal help bring the sellers’ price down from 100,000 to 10,000 Private Points. Afterward, she quietly admits that pretending to be Tatsuya’s girlfriend felt pleasant. Tatsuya later transfers her an agreed 30,000-point share of the money he receives from Sakayanagi Arisu, relieving her financial anxiety, though he reminds her that points alone will not protect her from failing the midterms. 35 37

Class Committee and Study Groups

Kei publicly backs Tatsuya’s bid for class secretary, urging the girls around her to support someone who can help the class avoid expulsions. She becomes a Class Committee member and joins its first meeting after accompanying Maya Sato and Matsushita Chiaki to Tatsuya’s room for tutoring. 40 43 44 45

The committee assigns Kei and Kushida to oversee the girls’ study group while Horikita coordinates the class-wide effort. Kei supports the plan, pressures Horikita to accept the coordinator role, and later rebukes classmates who want to avoid organized studying. Her score of 74 on a practice test reflects her own progress during the study campaign. 45 46 47 56

Illness and Personal Vulnerability

Kei visits Tatsuya after eight at night to report her practice-test result and show him her new manicure. He misses her attempt to solicit a compliment but notices signs of illness and gives her cold medicine. Back in her room, a mild fever and the sight of her abdominal scar bring back memories of middle-school bullying. She takes the medicine shortly after its expiration time, finding comfort in Tatsuya’s promise to protect her and his decision to entrust her with a committee role. The next morning, she brings him strawberry milk in thanks, and his compliment on her nails leaves her flustered. 56 57 58

Birthday Outing and Later Study Debate

Despite the approaching midterms and an expanded exam scope, Kei rushes to meet Tatsuya when he invites her to KTV on his birthday. She brings chocolates, is embarrassed when Hoshinomiya Chie mistakes the outing for a date, and joins a playful cake fight during an impromptu celebration with Hoshinomiya and Chabashira Sae. 59 60

After the midterms, Kei argues against classmates’ suggestion to buy the next exam’s questions, citing the expense of obtaining the previous papers and Class 1-D’s lack of available points. 71

Notable Quotes

“Then can you be my boyfriend? Oh, no, that's not right. I want you to pretend to be my boyfriend and protect me.” 14

“As long as you keep your promise, I agree.” 33

“Playing a gyaru like that would practically be me being myself, okay?” 34

“Still, pretending to be a couple with you felt pretty nice.” 35

“I swallowed expired medicine, hoping it could cure my past.” 57