Kai Matsui

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## Kai Matsui

* Anime
* Manga (Timeskip)

## Character Information

### **Also Known As**

Shorty-san (by Tsukishima and Oikawa)
Short stack/Short stuff (by Coach Ukai, Tanaka, and Tsukishima)
Idiot (by Kageyama)
Lil' Sis (by Kado)
Kichona-chan (by Karasuno and Kado)
Golden Girl (by various)

### **Age**

15 - 16 (High School 1st Year)
21 (Fall 2017)
22 (Nov 2018)
25 (Summer 2021)

### **Height**

152.9 cm (5'0.2") - Apr 2012
155.4 cm (5'1.6") - Nov 2012
162 cm (5'4") - Nov 2018

### **Weight**

44.2 kg (97.4 lbs) - Apr 2012
55.2 kg (121.6 lbs) - Jul 2020

## Background Information

### **Goal**

To make her older brother proud
To meet the same boys who made fun of her when she was younger and prove them wrong

### **Likes**

Volleyball
Boba
Wagyu Sando
Stars

### **Dislikes**

People underestimating her
Tests

## Professional Status

### **Occupation**

High School Student (1st Year, Class 3) - 2012
V.League Division 1 Player

### **Teams**

Little Falcons (Former)
Kitagawa Daiichi (Former)
Karasuno High (Former)
MSBY Black Jackals (Current)
Japan National Team (2021)

### **Number**

11 (Elementary 2nd Year)
11 (Junior High 1st Year)
4 (Junior High 3rd Year)
13 (High School 1st year)
4 (High School 3rd year)
15 (MSBY Black Jackals)
12 (2021 Japan National Team)

### **Position**

Libero (Junior High)
Opposite Hitter (Current)

## Image gallery

**Kai Matsui** (Japanese: **松井会***Matsui Kai*) is one of the two deuteragonists of the *Haikyū!!* series. For most of the series, she was a first-year at Karasuno High School, playing as the opposite hitter for the boys' volleyball club. She was known as the "Golden Girl" after her brother, who was named "Golden Boy". She's a volleyball prodigy being known by most highschool volleyball clubs and professional teams in Japan. She was chosen to train at an all-Japan youth training camp in her first year of high school along with Tobio Kageyama. After graduating from high school, she moved in with her older brother and his wife. After two years, she started playing as an opposite hitter for the MSBY Black Jackals, a Division 1 team in the V-League.

## Appearance

While entering high school, Matsui was the shortest member of her team, being 152.9 cm and slowly growing to the height of 155.4 cm throughout the school year. She has a relatively mature build, which is usually covered up by her oversized clothing. She has long black hair that stops near the middle of her ribcage, leading her to have her hair in a ponytail during matches. She also has fierce golden eyes, resembling those of an eagle.

Matsui typically dresses in her Karasuno school uniform with a black blazer, a white button-up short-sleeved shirt, and a grey skirt. Much like Hinata, beneath her blazer and over her button-up shirt is a light blue hoodie. Her legwear consists of black thigh-high socks and white laced sneakers. She's sometimes seen wearing her light blue hoodie around her waist with the blazer inside her backpack.

During matches, Matsui wears her volleyball uniform—a black jersey and the same colored shorts with white and orange stripes on the sides. On the back of her jersey is her position number, 13, (the same number as her brother's back when he played for Karasuno) and her school's name written in kanji. On the court, she wears kneepads and black volleyball shoes with white stripes.

## Personality

Matsui has a quite laid-back demenor sometimes. However, she can be quite cheerful for various reasons. She can be cheerful when being around her brother, being around her teammates, meeting other high schools, or just volleyball in general. She gets way too excited to the point where she's jumping up and down and yelling happily.

Matsui is known for playing on boys' teams. She does this so that people won't underestimate her and say she's not strong like the boys, as she was bullied for that when she was younger. As a former member of the Kitagawa Daiichi volleyball club, some of her former teammates teased her for being on the team until they saw what she was capable of as the libero. She got sick of people underestimating her so when she got to high school, she joined the Karasuno High boys' volleyball club.

Her older brother, the well known Golden Boy, Kado Matsui, helps her with volleyball so that she could get even better than she already is. They are also sometimes seen skateboarding together in their free time, as well as playing volleyball. She's grateful to have a brother like Kado and does almost everything with him.

She's ecstatic about sports and athletes. She knows about every famous volleyball player. The reason she loves volleyball so much is because she grew up playing that one specific sport, according to her brother. As stated by her teammates, she's one of the best players on the team. Her loving volleyball so much and making sure her teammates never give up, gives the team more confidence.

She rarely gets angry or upset. However, when she gets angry it's usually because someone cheated during a match or someone's teasing her. When someone teases her, she's quick to defend herself and fight back. She can also be sassy when people tease her which Tanaka finds funny. Whenever there's a serious situation, she's trying to help solve it and create less commotion and issues.

Even though Matsui is surrounded by noise most of the time, she's not really annoyed because she knows she can be loud at times as well. She hates studying, but when she has to, she prefers it to be calm and quiet rather than loud. She studies with the boys often and that's why she's used to the loud yelling and shouting. She'll sometimes tell them to be quiet or to shut up because she can't concentrate properly.

## Background

Matsui started playing volleyball during nursery school due to seeing her mother and brother playing together. She soon met Tobio Kageyama as a second year at Akiyama Elementary. Kageyama was getting bullied and she stood up for him. She saw him playing volleyball by himself once and offered to play with him and they became best friends ever since. When she entered Kitagawa Daiichi Junior High, her volleyball skills became much better with the help of her brother, Kado Matsui, and Kageyama. Her former teammate, Tōru Oikawa, was impressed with her skills and gave her some encouraging words to help her grow stronger as she had already looked up to him. She was given the nickname, "Golden Girl", after her brother, who was nicknamed, "Golden Boy". However, as soon as she got to her third year of junior high, people started recognizing the name as one of victory instead of after her brother.

In her third year of junior high, she became the captain of Kitagawa Daiichi's boys' volleyball club. She was known for playing on boys' volleyball clubs to prove that just because she's a girl, doesn't mean she isn't as strong as the boys. The boys were upset about her being the captain because she was a girl but was soon proved wrong as she showed them what she was capable of as a libero. At the Junior High Athletics Meet, her team's first match was against Hinata's team, Yukigaoka Junior High School. Before the game began, she and Kageyama went to the bathroom area, where they encountered Hinata being bullied by members from Kitagawa Daiichi. Kageyama coldly criticized them before turning his attention to Hinata, Matsui doing the same trying to match Kageyama's energy to seem cool. Despite Kageyama and Matsui's mocking of Hinata's lack of height and overly idealistic ambition, Hinata wasn't fazed and challenged the both instead, surprising Matsui and irritating Kageyama. While Kageyama accepted and angrily left, Matsui secretly wished Hinata good luck which confused him.

As expected, Kitagawa Daiichi easily made Yukigaoka nervous with Matsui's brilliant plans and practices before the event happened, but Hinata remained determined. Matsui was surprised that she found someone who uses a jumping technique like her; both Matsui and Hinata are short so she admired the fact Hinata used the same technique. In the end, Kitagawa Daiichi won both sets (25-5, 25-8). As the teams lined up, Kageyama angrily asked Hinata what he had been doing for the past three years while Matsui looked at Hinata pitifully before both got called away. Afterward, as they were leaving, Matsui and Kageyama were talking about hanging out with each other until Hinata ran up to the two and vowed to defeat both of them next time. Kageyama accepted his challenge, not taking it seriously, while Matsui smirked and said something along the lines of, "You're on!". Kitagawa Daiichi moved forward with the tournament, but lost at finals; it's hinted that Kageyama may be one of the main reasons for the loss due to his picture being on an article about the match but Matsui, being his only best friend, wasn't mad at him at all and was proud of him nonetheless.

At the junior high competition in her third year, she was ashamed of her team for wanting Kageyama on the bench. She was the only one who spiked his toss when he sent it to her teammates. Kageyama was then benched and ended his final game at Kitagawa Daiichi in shame and with Matsui scolding the rest of the team in anger, disbelief, and shame afterward. She believed that it wasn't Kageyama's fault for Kitagawa Daiichi losing, but the rest of the team's fault for wanting the only setter to be benched.

## Plot

### **Karasuno High Team Formation Arc**

Matsui and Kageyama arrive at the second gymnasium early to practice serves. Suddenly, the door slams open and Hinata rushes in, loudly asking Matsui and Kageyama why they are there as well. Matsui immediately recognizes Hinata and jumps over to him happily. Matsui quickly apologizes to Hinata about her cold and rude behavior before the Junior High Athletics Meet and compliments him on his jumping techniques. Kageyama insults Hinata and Matsui hits Kageyama on the shoulder, leading to an argument. Hinata asks Matsui and Kageyama why they're there and Kageyama reveals solemnly that he didn’t get into the best school in the prefecture. Matsui stated that she was going to apply to a different school but once she found out Kageyama got into Karasuno, she applied for it instead, wanting to be by Kageyama's side like she promised.

Daichi, Sugawara, and Tanaka are walking in while talking about both Matsui and Kageyama. They greet the two and talk to them for a bit. Hinata loudly greets the third years and Tanaka, taking the attention of Matsui and Kageyama momentarily. They compliment Hinata for his performance last year and he exclaims that he’ll become Karasuno’s ace. This causes Kageyama to insult him, reminding him to not waste another three years again and Matsui scolding Kageyama and hitting him once more. Daichi tries to stop the argument but Kageyama and Hinata ignore him, too engrossed in their fight. Matsui steps away from them and stands next to Daichi. She stated that the same thing happened before the third years and Tanaka came to the gym.

The vice-principal then comes in and the upperclassmen and Matsui try to cover up the situation, but Hinata and Kageyama end up challenging each other to a mini-match. Hinata exclaims that he’s not the same as last year and Kageyama replies with the same words and smiles excitedly, surprising both Matsui and Hinata. Matsui thought to how Kageyama doesn't smile around others except for her and his family. She momentarily is proud of him for smiling around other people for the first time in years.

The match begins and Kageyama does a jump serve that Hinata avoids at the last moment and Matsui watching closely, anticipating the two's moves. Kageyama asks if this behavior is any different from last year’s and Hinata asks for another try without any hesitation. Kageyama serves again but to his surprise, Hinata moves quickly to where the ball goes and Matsui looked surprised, wondering how much speed Hinata has. However, the ball bounces off his arms and then his face before flying towards the vice principal. It knocks the vice principal’s wig off, silencing everyone in the gym. Matsui stifles a laugh and looks down, trying to cover up the fact that she wanted to burst out laughing. Coldly, the vice principal asks Daichi to go outside for small talk as Kageyama, Hinata, and Matsui watch on.

When Daichi returns, he rounds everyone up and begins lecturing the first years before getting cut off by Kageyama. The setter criticizes Hinata and blames him for everything and Matsui facepalms while Daichi interjects coldly. He explains Karasuno’s goals to go to Nationals before asserting that he doesn’t want any players on his team who would fight with one another. He then throws the two first years out and let Matsui stay inside due to her not picking a fight with neither Kageyama nor Hinata. The two other first years aren’t allowed to join until they begin to view each other as teammates.

Daichi then continues on to ask Matsui why she isn't with the girls' volleyball club. She tells him that she wants to prove to the world that just because she's a girl doesn't mean she isn't as capable as the boys are due to her being teased her whole life about being a girl wanting to play volleyball. Sugawara quickly recognizes Matsui as the volleyball prodigy nicknamed Golden Girl and realizes that his senior when he was a first year was Matsui's older brother, Kikichu, also known as Golden Boy. Daichi and Sugawara ask Matsui how Kikichu is doing and Matsui happily responds.

Daichi then declares that in order for Matsui to officially join the boys' volleyball club, she has to participate in a match with the third years and Tanaka. Tanaka will be on her team, and Sugawara and Daichi will be on the other team. Matsui immediately agrees and accepts the challenge. Tanaka then noted that Matsui seemed like a good person to hang around because of her cheerfulness and how she was so determined to do anything.

After the match, Matsui and Tanaka end up winning due to Matsui gaining the points for her team with Tanaka setting for her to strike. Daichi congratulates her and awarded her as being officially being apart of Karasuno's boys' volleyball club. Matsui was very happy, jumping around and fist-bumping the other three. They all started to clean up the gym. Matsui shortly exits the gym to tell Kageyama and Hinata about what happened. Kageyama was genuinely proud of her and hugged her then doing a handshake they made up when they were younger while Hinata jumped up happily asking Matsui if she can teach him her ways someday. She laughed and happily agreed before going back inside the gym.

#### **3-on-3 First Years Match**

Later on in the evening, as the Karasuno members (including Matsui, the newest member) are cleaning up, Hinata and Kageyama announce their challenge. Secretly, Kageyama still refuses to work with Hinata and may have been planning on winning the game with serves and dump shots only. Daichi sternly asks them if they had considered the possibility of them losing and Kageyama replies that they’ll take any punishment. Matsui quickly joins in the conversation and questions why Kageyama isn't being the stubborn person he always is to which he replies that this is a serious situation.

Daichi agrees and changes the match to a 3-on-3 with the duo against the other two first years. Tanaka is placed on the duo’s team while Daichi joins the other one while Matsui will count points and analyze what they need to work on. However, if the duo loses, as long as the third years are around, Kageyama will never get to play as the setter. A shocked Kageyama tries to reason as Daichi reminds him of his selfish behavior from junior high. Matsui was shocked knowing that Kageyama was best as a setter which is why her junior high team lost last year from him being benched. Despite Daichi telling him that he can join the club as another type of player, Kageyama exclaims that he is a setter only to which Matsui agrees to out loud explaining why her junior high team lost. Daichi replies that it’ll be okay as long as Kageyama wins, and the latter accepts begrudgingly.

## Statistics

 Stamina
 Game Sense
 Technique
 Speed

Matsui is described as strong and smart when it comes to sports. She thinks through the game and knows what's good and bad. She's pretty serious about sports as if it's very important, which it is for her. Matsui's known as the "Golden Girl" after her older brother, the Golden Boy, and her many wins. She's golden because she's lucky to have won along with her team and she's very proud of that. She's improved throughout her time at Karasuno, making her well known to other schools. It is said by Oikawa, a former teammate, that she's way better in volleyball now than when she attended Kitagawa Daiichi.

**Height and reach, as of mid-November 2012:**

* Fingertip Height: 205 cm
* Jumping Reach: 342 cm (spike) / 327 cm (block)

### **Skills**

* **Jumping**: Matsui has an extremely great jumping power to spike. Since she's short, she can jump very high which is great for her, which is why she has no complaints about being short. She can jump to as high as Lev's height or even higher. She learned most of her jumping techniques from the help of Hinata, who also has amazing jumping skills. In addition to Hinata helping her, she has helped him learn some other techniques.
* **Golden Spike**: Her Golden Spike is when someone tosses the ball to her (she made this move up with Kageyama during their time in junior high so he was the person who usually tosses the ball) and she spikes it, earning a point for her team (that's where she gets the name from; "Golden" as in winning or victory). When someone tosses her the ball she immediately runs to the right side, jumps up high, and spikes the ball with an extremely hard hit, earning a point, as none of her opponents were able to spike back because the ball comes at an extremely hard force.

## Trivia

* Favorite Food: Wagyu Sando

* Current Concern: She feels like she won't be able to beat Kenma in one video game.

* Matsui's star-sign is a Cancer as she was born on July the 5th.
* Matsui attended Kitagawa Daiichi Junior High along with Kageyama. Matsui and Kageyama were best friends since grade school.

* Matsui broke a bone in her knee while playing tag with Kageyama when they were younger. She had tripped over a rock and fell with Kageyama immediately running to get help after checking if she was okay first. The broken bone doesn't have an effect on her playing volleyball as it is perfectly healed now.
* Matsui strongly dislikes when somebody says that she's not strong because she's a girl.

* Matsui is shown to not be all that smart and fails most of her tests.
	+ Matsui's worst subject is English.
		- According to her, she has always hated English since grade school.
* Matsui is the second-oldest first year on the team, the oldest being Hinata.
* Matsui is notably petite but has a very strong body.
	+ Matsui has strong muscles, her strongest muscles being in her thighs.
* She's the younger sister of the well known Golden Boy, Kikichu Matsui.
* Matsui enjoys watching anime, especially the ones with the action or sports genres.
* Matsui's looks are compared to those of a black eagle due to her black hair and golden eyes.
* Matsui's mother used to play lots of sports when she was in high school which is where Kikichu and Matsui got their love of sports.
* Matsui's name was originally supposed to be, **Hoshiko Matsui**. Hoshiko written in kanji is, (星子), which means 'star, child'.
	+ Matsui is shown to have a great love for stars which is why her first name was originally supposed to be Hoshiko.
		- Her favorite activity is stargazing.
* In Haikyū!!: One-Shot, Matsui's jersey number was 5, instead of 13.
* Matsui's jersey number in her first year of Karasuno was the same as her older brother's when he attended Karasuno.
* Nekoma High was the first school Matsui was going to apply to until she found out Kageyama was applying to Karasuno High. She wanted to stay by Kageyama's side as she cared for him deeply so she decided it'd be best to apply to Karasuno along with Kageyama to feel complete.
* The entire Nekoma High volleyball team has complimented Matsui's looks saying she was very pretty, especially Lev, Kenma, Kuroo, and Yaku.
* Matsui realized she had a crush on Kenma and soon confessed to him. They started dating while Matsui was in her second year of high school and Kenma was in his third year of high school.
* **Nomenclature:**
* Kai (会) - *lovable, worth*
* Matsui (松井) - *real, true*