Kei Tsukishima (Japanese:
Tsukishima is very tall and has an incredibly slim build for a volleyball player. Despite being a first-year, he is the tallest player in Karasuno High, standing at 190.1 cm. He has short blond hair, pale skin, thin eyebrows, and golden-brown eyes. He is often seen with a frown or a condescending smirk on his face.
After joining the Karasuno volleyball team, Tsukishima wears the standard Karasuno volleyball uniform (black, orange, and white uniform with the number 11 on the back) during matches. He also wears knee pads and white volleyball shoes with green details. He is also the only player on the Karasuno team who wears glasses. Since Chapter 109, Tsukishima began wearing prescription sports glasses (a gift from his older brother, Akiteru) in matches.
Outside of matches and practice, Tsukishima wears a black gakuran, the Karasuno male uniform. He is usually seen with white headphones around his neck. The brand of these headphones seems to be "Somy", which is a play on the real name brand "Sony." He has been seen wearing various shirts with crescent moons on them, which plays on his name "Tsukishima" with "tsuki" meaning "moon".
Tsukishima is very blunt and will sometimes rile his teammates up due to his antagonistic nature (most notably being Hinata, Kageyama, Nishinoya, and Tanaka) and sometimes other teams because of his casual smug attitude, taking pride in and relishing when his opponents see him as a nuisance as seen with Tendō and Shirabu.
Whenever someone does or says something stupid or silly he is usually seen snickering in the background. However, he does seem to be intimidated by his seniors, being nowhere in sight when Daichi reprimands Tanaka for antagonizing Aoba Josai even though he did so as well, or backing down whenever Ennoshita calls him out.
Despite coming across as arrogant, Tsukishima has low self-esteem and thinks of himself as inferior. This is first noted to be a surprise by Kuroo, who accidentally riles him up by suggesting he’ll lose to Hinata, to which he says that he’s already below him. After the Shiratorizawa match, despite being the MVP, he’s seen calling himself lame for only being able to block Ushijima’s spikes once, only adding to how little he believes in himself and his achievements.
Although Tsukishima maintains a persona of someone who shows little interest in anything and wouldn't do something he didn't like or enjoy, he does truly enjoy volleyball. He initially refrained from putting too much effort into volleyball and being too passionate about it out of fear of suffering from the same fate as his brother. However, after his confrontation with Yamaguchi and hearing Bokuto's inspirational words in the Tokyo training camp, he started to take the sport more seriously and finally found his passion and motivation for volleyball when he blocked Ushijima.
Tsukishima keeps his cool, for the most part, but he can be seen getting visibly annoyed when people underestimate him or tell him what he can or can not do, and uses it as motivation to prove them wrong. He also says things like "It's not a competition" with Hinata but then immediately proceeds to do something to make him jealous, such as the time difference attack during the Shiratorizawa match.
According to Akiteru, "Kei is blunt and doesn't show his emotions often, but he is actually a very hardworking and kind boy."
BackgroundTsukishima was a lot more cheerful when he was younger and had a very close relationship with his older brother, Akiteru Tsukishima. As a young child, Tsukishima seemed to really like volleyball, arguably due to his older brother’s own love for the sport. However, Tsukishima’s attitude towards volleyball (and club activities, in general) changed when Akiteru entered high school and became a member of the Karasuno High Volleyball Club.
Despite practicing very hard, Akiteru failed to become a regular player for Karasuno due to the number of more talented players on the team, including Hinata’s idol, the “Small Giant.” Seeing his older brother’s disappointment, Tsukishima began to think that he shouldn’t put so much effort anymore, like his brother did, to avoid being disappointed if he fails.Sometime in elementary school, he sees Tadashi Yamaguchi being bullied. He doesn't do anything, except call them pathetic. This was aimed at both Yamaguchi and the bullies. After seeing how Tsukishima could stand up to the bullies so easily, Yamaguchi starts to look up to him.
Karasuno High Team Formation Arc
3-on-3 First Years Match
Tsukishima and Yamaguchi join Karasuno Boys’ Volleyball Club a few days after it begins for the new school year. That evening, they go to where Hinata and Kageyama are practicing. To mess with Hinata, Tsukishima goes behind him and grabs the ball before Hinata can catch it and asks if the two are the first years who caused problems. When Hinata tries to reach for his ball, Tsukishima adds that elementary school kids should be going home, annoying Hinata.Kageyama cuts in and asks how tall Tsukishima is, though Yamaguchi answers for him. Tsukishima then points out Kageyama’s junior high and wonders what an “elite” is doing at Karasuno. Hinata calls for Tsukishima’s attention again and declares that they aren’t going to lose the 3-on-3 and Tsukishima simply shrugs it off, surprising Hinata. Lightheartedly, Tsukishima explains that the match isn’t important for him and Yamaguchi so they could just throw the game for them if they want.
Angered, Kageyama replies that no matter what Tsukishima does, he would still win. In return, Tsukishima laughs at his confidence and reminds him of his “King” nickname. As Kageyama tries to retort, Tsukishima continues bringing up his past and remarks that it’s true Kageyama dislikes his nickname. Kageyama has had enough when Tsukishima brings up his performance during the prefecture semifinals last year and lunges forward, grabbing Tsukishima by the collar.
After a few seconds, Kageyama lets go and simply walks away, causing Tsukishima to mock him even more. Suddenly, Hinata jumps up behind him and grabs the ball out of his hand, shocking him. As he lands, Hinata exclaims that he will defeat Tsukishima. Losing his composure for a second, Tsukishima glares at him, but quickly recovers and frivolously states that they should just have fun since volleyball is just a club anyway. He then walks away, leaving a confused Hinata staring after him.
On the way home, Yamaguchi runs to Tsukishima and asks him what’s wrong since he seems to be brooding. Coldly, Tsukishima replies that he hates uselessly hot-blooded people like Kageyama and Hinata.
On the day of the 3-on-3, as the players are warming up, Tsukishima loudly provokes Kageyama and Hinata to make them lose their composure, prompting Daichi to comment that Tsukishima has a bad personality.At first, Tsukishima easily blocks Hinata’s spikes due to his height advantage and makes a point of emphasizing that and Kageyama’s past. While Kageyama does his best to ignore him, Hinata gets angry and confronts Tsukishima, who reveals that Kageyama is only called a King because of his horrible attitude towards his former teammates. To his surprise, Kageyama responds that he is actually terrified of tossing the ball and not seeing anyone behind him like what had happened in junior high. Hinata quickly jumps in and adds that he doesn’t care about Kageyama’s past and will hit any ball Kageyama sends to him. Annoyed, Tsukishima replies that Hinata’s genuine straightforwardness irritates him and reminds Hinata that he can’t fill the gap in height with fighting spirit.
Throughout the game, Tsukishima continues with his taunts, reminding Hinata that he can’t just accomplish anything he wants just by putting all his effort into it. Hinata acknowledges that, but responds that he still wants to win with his body. As Tsukishima adds that his height is still an obstacle, Kageyama cuts in and states that as a setter, he will clear the path for Hinata.
When Hinata and Kageyama pull off their first planned quick, Tsukishima’s shocked to discover that Hinata had his eyes closed and asks Daichi to explain it. After the two fail their next tries, Tsukishima wonders how long they’re going to keep trying until they give up. Daichi adds that it’s hard to see someone trusting someone else so completely, especially a rival.
The next try, Tsukishima states to Kageyama that he should stop tossing to Hinata since it’ll always fail. However, he’s unnerved to see Hinata run up to Kageyama and quickly calls Yamaguchi over, leaving Daichi in the back. Hinata spikes successfully and scores.
In the end, Tsukishima’s team loses. After the match, Hinata goes to Tsukishima and holds out his hand, seemingly asking to make up because the upperclassmen will kick out any members who don’t get along with others. Tsukishima ignores the hand and retorts that he only got kicked out because he ignored the upperclassmen and caused chaos.
After Hinata leaves Tsukishima, Daichi approaches him and asks him what he thought of the match. Tsukishima replies that he didn’t really care and knew he would lose since he was against Kageyama. Daichi grins and points out that Tsukishima still got pretty serious during the game.
At that moment, Kiyoko walks in with the team jackets. At first, Tsukishima doesn’t want to put it on, but Tanaka and Sugawara goad him into wearing it. Lining up, the first years stand in front of the upperclassmen with their jackets on and officially get welcomed into Karasuno Boys’ Volleyball Club.
Aobajohsai Practice MatchUpon their arrival at Aobajohsai High, Tsukishima, Yamaguchi, Tanaka, and Kageyama overhear two members of Aobajōohsai, Yahaba and Kindaichi, badmouthing Karasuno. Tanaka and Tsukishima join forces to intimidate the two Aobajohsai players before Daichi arrives to reprimand them.
Later during the match, Tsukishima is seen mocking Kageyama and Hinata after Hinata struck Kageyama on the back of his head with a serve. It's apparent that Tsukishima is still unable to get along with the his fellow first years, especially Kageyama. The two nearly get into an argument in the midst of a game after they started exchanging insults. Amazingly, they end up in-sync and put up a strong block after growing competitive toward each other. After their successful block, Tsukishima and Kageyama end up arguing over whose hand stopped the spike until Daichi angrily shouts at them to stop.
Towards the end of the match, the coach of Aobajohsai, Irihata, describes Tsukishima as a clever blocker, despite being somewhat lacking in drive. When Oikawa, Aobajohsai’s captain and setter, arrives to pinch serve for their team, Tsukishima is targeted specifically for his weakness in receives. He grows frustrated after continuously failing to receive Oikawa's serve. He becomes even more annoyed when Hinata stands up for him and gives him a speech about being allies. Afterwards, Tsukishima finally makes a save off of Oikawa's serve but ends up sending a free ball back to Aobajohsai. However, his efforts ultimately gives his team a fighting chance, and they are able to capitalize on it to win the match.
Later when Karasuno is leaving, Oikawa stops them and point out Tsukishima and Hinata's need to work on their receives. He is shown to be uncooperative when Hinata proclaims that they will be doing special training.
Asahi and Nishinoya's Return
Nekoma Practice Match
Tokyo Expedition Arc
Shortly after Karasuno was defeated by Aobajohsai, Takeda announces that, thanks to Nekoma's coach, Nekomata, Karasuno will have a practice match in Tokyo against Nekoma and other schools in the Fukurōdani Academy Group. However, members of the team need to pass their final exams (and avoid having to take supplementary classes) if they want to join the practice matches.
Having learned that Tsukishima belongs to a college prep class, Hinata and Kageyama, who are bad at studying, ask Tsukishima to teach them. Tsukishima initially refused, but eventually agreed after Kageyama begged him to teach them. However, Tsukishima only agreed to teach Kageyama and Hinata before and after practices. He also eventually stops teaching the two because he claims they were both too stupid to understand the lesson.
In Tokyo, while the rest of his teammates are trying to individually improve, Tsukishima is shown to have no interest in improving his blocking. One night, through some coaxing by Tetsurō Kuroo, Tsukishima joined (albeit reluctantly) the blocking/spiking practices between Kuroo and Fukurōdani's Kōtarō Bokuto and Keiji Akaashi. He quickly leaves, however, when Kuroo teases him about Hinata. Kuroo observes that Tsukishima, despite being a lot taller than Hinata, actually feels inferior to the latter.
Through a flashback, it is eventually revealed that the reason behind Tsukishima's dispassionate attitude towards club activities and inferiority complex towards Hinata is the experience of his older brother, Akiteru, as player for the Karasuno Volleyball Team. After a confrontation with Yamaguchi, however, Tsukishima begins to change his outlook and starts improving his blocking with the help of Kuroo and Bokuto.
Spring High Preliminary Arc
Tokyo Nationals Arc
Tsukishima is shown to be immensely proficient at blocking primarily because of his height. It has been said by Kenma that Tsukishima is a calm and collected blocker who thoroughly analyzes his actions, quite contrary to Hinata's behavior. His ability also allows him to perform split-second feints to surprise and put his opponents off-balance. After the final training camp before the spring tournament, he is able to match the power and speed of an adult, whereas before he couldn't even hold the block.
Height and reach, as of mid-November::
- Fingertip Height: 248 cm
- Jumping Reach: 334 cm (spike) / 325 cm (block)
- Blocking: Tsukishima has established himself as the blocking cornerstone of the team and is often trusted to stop opponents' powerful spikes. He learns most of his blocking skills from Tetsurō Kuroo, who is known to be a veteran in blocking, during the Tokyo summer training camp. There, he learns about putting power into the tips of his fingers and extending his hands out in front of him instead of above him. In addition, he has practiced with his brother's college team to match the timing of his opponents' spike. In matches, he has become the team's blocking playmaker and directs other blockers in his line. With a height of 190cm, Tsukishima has proven to be a troublesome opponent to many spikers. He is said to be the “freak quick killer” by Coach Ukai simply because of how Tsukishima has had to constantly deal with the quick, and as such has gotten used to and sick of it altogether.
- Logical Mind: According to Akiteru, Tsukishima isn't the sort of player who moves on instinct. He doesn't trust in his own strength, nor in the senses, he's honed. The only thing he trusts is the "information" in front of him. As such, he rarely falls for opponents' decoys, including the One Person Time Difference attack. He is quick to process all the players' information and deduce where the toss will go to put up a strong block. This ability makes Tsukishima an exceptional read blocker. In addition, Tsukishima has shown an incredible ability to stay cool-headed. During the Inarizaki match, he persists in restricting Suna's spiking course for the benefits of his team despite many other admitting that they can't resist going for a direct block. Takeda has referred to him as "Karasuno's rational mind." 
- Feint: Tsukishima has used a strategy in which he repeatedly feints to trick his opponents into moving forward. Once that happens, he would change to a normal spike aimed at the newly empty space on the court. 
- One Person Time Difference Attack: It is revealed that Tsukishima acquires this skill practicing with Akaashi during the Tokyo summer training camp. He successfully pulls off this attack during the Shiratorizawa match, in which he tricks the blocker with a delayed jump before spiking.
- Tossing: During the 2-on-2 matches in the Miyagi First Years' Training Camp, Tsukishima is forced to toss. Initially, his toss is too low and sloppy, but he quickly made adjustments after complaints from Goshiki. He can now send high tosses to Asahi, although he still credits it's success mostly to luck.
- Akiteru Tsukishima: Tsukishima has an older brother named Akiteru, who was a member of Karasuno's volleyball club at the same time as the Small Giant. Akiteru is both the reason for Tsukishima's interest in volleyball and his current attitude towards it, namely the idea that one should not put too much effort into his club activities because he will only end up getting hurt in the end. Tsukishima used to adore his brother and would often ask him to teach him volleyball skills as soon as Akiteru got home. However, their relationship was destroyed when Akiteru lied to Tsukishima about him being an ace on his team only for Tsukishima to find him in the bleachers during a match. Since then, Tsukishima would avoid talking to Akiteru and whenever the latter came home from college, Tsukishima would lock himself in his room until dinnertime.
After the summer camp in Tokyo, the brothers finally talked to each other about their past and reconciled based on it. They are now slowly putting their relationship back together.
- Tadashi Yamaguchi: Tsukishima is shown to be close friends with Yamaguchi, who calls him by his nickname Tsukki. When they were younger, Tsukishima rescued Yamaguchi from bullies by calling them pathetic. Because of this, Yamaguchi later became attached to Tsukishima, yearning to be as cool as him.
Yamaguchi and Tsukishima are rarely seen apart. They are both often portrayed making fun of others together. However, as time went on, their relationship began to drift apart in terms of training. While Yamaguchi persevered in working on his jump float serve, Tsukishima did not exert more effort than needed. This worried Yamaguchi and some of the other members, but they didn't say anything at first. Later on, in the summer training camp arc, Tsukishima still refused to put any effort into his training because he did not see why he should. His behavior angered Yamaguchi who for the first time yelled at Tsukishima, asking him what more motivation he needed than pride. This changed Tsukishima's way of thinking and impressed him; he even called Yamaguchi "cool" for the first time. Tsukishima started working harder, and their relationship returned to normal after this event.
- Shōyō Hinata: Tsukishima initially had a rather antagonistic treatment towards Hinata. He has voiced his dislike of the latter's hot-blooded nature towards volleyball despite his lack in height—even going through the lengths of trying to crush Hinata's spirits during their 3-on-3 match at the start of the series. This is later revealed to have been because of his brother's volleyball history in Karasuno.
Tsukishima also has originally considered himself somehow inferior to Hinata's skills, as noted by some of their teammates and Kuroo. After finding his own love for the sport, Tsukishima has started to have a bit more of a competitive rivalry with Hinata, as the two are both middle blockers.
- Tobio Kageyama: Tsukishima and Kageyama didn’t get along at all, mainly because they got off on the wrong foot in the beginning. Tsukishima uses Kageyama's past as a terrible teammate to insult the latter often, and Kageyama would often yell back; their fight almost led to violence at one point. Tsukishima was shocked by Kageyama's change at first, especially when Kageyama asked him about the type of toss he preferred. Since then, the two now view each other as teammates and work together during matches, capable of performing time-difference attacks, as well as working together as part of Karasuno’s “total defense.”
- Karasuno High: As far as his relationships with his teammates go, they vary though he holds a few members with disdain. For starters, he looked down on both Kageyama and Hinata, the former for his infamous reputation as the bossy king of the court (even calling him by that moniker just to mock him) and the latter for both his short stature and hot-blooded demeanor. This disdain also applies to his second-year senpais Tanaka and Nishinoya, who are also hot-blooded (a trait he found irritating). However, he did hold respect for his third-year senpais Daichi, Sugawara, and Asahi but probably on the account that they are more level-headed. However, before being reprimanded by Yamaguchi for not trying his best, he felt that the team's efforts to improve were futile and thought that in the end, they'll still lose anyway. Unlike the majority of his teammates, Tsukishima is not really attracted to Kiyoko nor did he interact much with her so far.
- Tetsurō Kuroo and Kōtarō Bokuto: During the summer training camp arc, Tsukishima trained with Kuroo and Bokuto at their request. In their training matches, Tsukishima received advice from both of them while also paying deep attention to their moves. The two are mainly responsible for Tsukishima's improvement; Kuroo taught Tsukishima the proper way to block successfully and Bokuto taught Tsukishima "that moment", which Tsukishima used as motivation in the Shiratorizawa vs Karasuno match. After the training camp ended, Bokuto and Kuroo started calling Tsukishima by his nickname 'Tsukki', much to his annoyance.
- Favorite Food: Strawberry shortcake.
- Current Concern: Upon entering high school, he once again has to put up with various people asking how to read the character for his first name.
- The character for his name (蛍) means firefly and can be read as either Hotaru or Kei.
- Tsukishima wears white gym shoes with green accents.
- His star sign is Libra.
- He has the third-smallest appetite in the series, often making his teammates and upperclassmen worry for his health.
- His BMI is the lowest of the male characters in the series.
- He has a habit of fiddling with his fingers when he feels nervous, which is demonstrated most notably when he asks Coach Ukai for advice on blocking.
- He is usually seen with his white Sony (Somy in anime, to avoid copyright issues) headphones around his neck whenever he's not practicing or playing.
- Tsukishima appears to be good at studying, as he belongs to Class 1-4, known to be a college preparatory class.
- His birthday falls on the day of the Harvest Moon–which is when the Mid-Autumn Festival, also known as the Moon Festival, on the Chinese calendar is celebrated in September 2015. Coincidentally, the first character in his name means "moon". In addition, Tsukishima was often seen with a crescent moon symbol on the back of his hoodies and jackets as a child.
- He keeps toy dinosaurs on a shelf above his desk. Whether he actually likes dinosaurs or not is unknown, but it can be assumed that he does, as is demonstrated in a Let's! Haikyuu!? chapter.
- Tsukishima is often referred to as the moon while Hinata is the sun due to their surnames and opposing personalities.
- In a poll conducted by Charapedia, a Japanese anime and manga character database, that asked which anime characters would they choose as the basis for their children's name, Tsukishima came in 9th with 98 votes among female respondents.
- In Haikyū!!: One Shot, Tsukishima was a second-year while Hinata and Kageyama were first years. He was also only 184 cm.
- Furudate picked Tsukishima's name because “His last name has ‘moon’ (月) to contrast Hinata’s ‘sun’ (日). But I named him ‘firefly’ (蛍) because he can emit light on his own.”
- In Haikyuu's first popularity poll, Tsukishima placed 8th with 3,407 votes. In the second, he rose to 4th with 8,305 votes.
- Kei (蛍) - Firefly
- Tsukishima (月島) - Moon Island