Hayama is of average height and build. He is shown to be very agile and athletic. He has short, blond hair and a pair of oval-shaped eyes with dark pupils. He also has a snaggle tooth in the right corner of his mouth. He wears the blue and white Rakuzan jersey with the number 7.
Hayama is energetic to the point of annoyance. He often fools around carelessly like a child, causing his teammates to sometimes scold him.. In addition, he seems to yell most of his sentences instead of speaking at a normal volume. Despite his carelessness, Hayama is very spirited about basketball (and sometimes other sports like skateboarding) and enjoys going against strong opponents, becoming excited when he gets a chance for a one-on-one. He is also an attention-seeker and enjoys showing off his dribbling skills to his team and opponents. Hayama does not seem to be too sharp as is impulsive as he was easily tricked by Izuki to enter Kagami's field of range and also openly admitted his temper gets the best of him.
Although he generally presents with an upbeat personality, Hayama hates to lose and has a tendency to be vengeful towards his opponents such as when Miyaji dribbled past him and Kagami totally dominated him while in the Zone; he requested Akashi to let him mark Kagami one more time for he can't settle down unless he returns the favor. He also takes pride in being an upperclassmen, as he tells Kagami he forgot to add Senpai after his last name.
Hayama was a very strong and talented player in Junior High school and was known for his Lightning Dribble, which earned him the nickname Raijū. However, he was overshadowed by the Generation of Miracles and instead bears the title of one of the five Uncrowned Kings.
Hayama and his team made it through the first round and the quarter-finals with no mention-worthy matches.
Before the Winter Cup semi-finals start, Hayama is seen visiting a sports shop. When Kagami enters the shop and climbs the stairs, Hayama is seen rushing down from it. Unable to stop, Hayama jumps, does a somersault and lands behind Kagami. Hayama apologizes and runs off, but not before Kagami can see his Rakuzan High sweater.
He later appears alongside his team, entering the gym for their match. When Hayama sees Shūtoku High, their opponent, he freaks out and shouts that they look super strong. This annoys Mibuchi. He directs his statement at Akashi and Akashi confirms that they are indeed strong. When the match finally starts, the ball goes to Takao. He is guarded by Hayama and surprises him by passing the ball behind his back.
The match goes on and the first quarter passes by. At the first attack by Shūtoku, Hayama finds himself guarding Miyaji in a one-on-one. He is excited to get some action but is set straight by Miyaji's dribbling and is passed. Hayama is scolded by Nebuya, Mibuchi, and Akashi, and he receives the ball during the counter. Guarded by Miyaji, Hayama smirks and guesses that "three" will be enough. He proceeds to bounce the ball extremely strong and fast, and then dribbles right past Miyaji. He goes up for the lay-up, but encounters Kimura under the hoop. He then performs a double clutch to avoid Kimura, and makes the shot. It is later revealed that his dribble from before only used three fingers. Miyaji is amazed to find out that there are still two stages above that.
The next offense, Hayama passes Miyaji again and passes it through to Nebuya, who later thanks him roughly for the pass. Hayama calls him a muscle gorilla, something Nebuya jokingly takes as a compliment. A counter by Rakuzan follows and Hayama passes Miyaji yet again, only to be blocked by Midorima during the lay-up attempt. Hayama is amazed by Midorima's speed. The first half ends with a tie.
The match continues and Akashi faces Midorima in a one-on-one battle. Akashi overwhelms Shūtoku, resulting in 71 - 51 for Rakuzan. Midorima starts combining his shooting with Takao's passing, slowly closing the gap. Hayama attempts to shoot a basket but misses which results in a Shūtoku rebound and possession of the ball. The players pass the ball to Midorima, who scores again. When Shūtoku regains their determination by slowly cutting into Rakuzan's lead, Akashi shocks everyone by scoring on his own team's basket. He tells his team that this is not the time to relax and that the match is not over yet. He states that if they lose by just one basket, it will have been his fault and that he will gouge out his eyes and give them to his teammates.
When the game resumes, the Rakuzan players appear more serious than before. Hayama gets the ball and scores a basket. The match ends with a score of 86 - 70, as Akashi shuts down Takao and Midorima's combination plays.
During the warm-up, the Rakuzan players settle on their marks, Hayama's being Kagami. All of the starting members are announced onto the court as they bow, wishing for a good match. The tip-off begins and Kagami gets the ball, he scores over Akashi using the Meteor Jam, everyone noticed that he has entered the Zone.
Hayama has displayed some exceptional athleticism in the form of speed and agility. In his introduction, he was able to easily somersault past Kagami. He can perform a near perfect double clutch, dive under a defender and lay it in. Hayama's defense is also stellar, as his extreme energy allows him to play an especially tight and intense defensive style. Both Kagami and Alexandra Garcia later observe that Hayama has mastered the control of his "animal instinct", heightening his reflexes and overall physical ability. His particular "animal instinct" has manifested in the appearance of a cheetah.
Hayama's speciality is dribbling. His ball control is of such high level, that he actually presses the ball downwards with force enough for it to explode perfectly into a quick cross-over. Because he slams the ball so fiercely onto the ground, it becomes too fast for eyes to follow, making it very hard to steal. If the ball has reached its top speed, it's as if the ball has disappeared. It's also shown the noise his dribble made is loud enough to be heard by spectators that covered their ears.
While his dribbling already is seen to be at a high level, this is shown to be only a portion of his power, as Miyaji observed that he had only dribbled with his three innermost fingers, hinting to two even greater levels of dribbling ability. During Rakuzan's match against Seirin High, Hayama passed Kagami with his power-dribble, this time using four fingers. This indeed seems like another upgrade of his dribbling ability and withholds a fifth level, which he uses against Izuki later on. The five fingers is far different than the other stages because the ball stays still in Hayama's hands even though his body is going for a drive. Then, lightning sparks appear as he starts to dribble, emphasizing his speed and agility. Izuki may have been able to see through his dribbling pattern, but remains unable to match his speed. Kuroko is forced to help on defense, luring Hayama into Kagami's sphere of defense, where he is blocked.
Hayama respects Akashi along with the rest of his teammates. However, he gets shocked from his behavior sometimes such as when Akashi promised to gouge out both his eyeballs as punishment if they lost against Shutoku. After every victory, he feels relief rather than elation because he knows Akashi won't penalize him or his teammates. During the Winter Cup Finals against Seirin, his relationship with Akashi excessively changes. When Akashi states he doesn't need them anymore, he feels shocked and upset. When Akashi breaks down, he is as surprised as the rest of his team and also loses trust in his leadership and ability to stay in the game. When Akashi's true self awakens, he became ecstatic as he joined them as their true captain and helps all of them enter the Zone.
Hayama seems to get along with the other Uncrowned Kings of his team as he is around them inside and outside club hours. He is also very affectionate towards them calling Nebuya and Mibuchi "Ei-Chan" and "Reo-nee" respectively. He and Nebuya seem to get along due to their shared care free attitude, while he and Mibuchi seem to be close due to the latter always looking out for him both as friends and teammates in a motherly way. Hayama is also close to and trusts Nebuya and Mibuchi enough to know when they are alright under pressure during a game or if they need to be redirected. Like the rest of the Uncrowned Kings on the team, he seems to have a strained relationship with Mayuzumi as the three might have initially doubted Mayuzumi's abilities as a player.
During the Winter Cup Finals, when he first faced Izuki, he thought he wouldn’t be as challenging as Kagami was. However, when Izuki breaks through his technique at full strength, he is shocked. Izuki admits that he knows he’s not stronger, but he is at least smarter than Kotaro. Falling for his taunt, Kotaro carelessly lets Seirin score. However, he calms down and decides to save the one-on-one between himself and Izuki for later. Furthermore, he is the only one yet who has laughed at Izuki’s puns.
- Hayama's first appearance in color initially had him with yellow hair. It was later changed to orange in the colored pages of the fourth Replace novel.
- According to the CHARACTERS BIBLE PLUS:
- His favourite food is Kappamaki.
- His hobby is skateboarding.
- His speciality is Horizontal bar.
- His motto is: "Strike while the iron is hot."
- According to KUROFES:
- His best subject is World history.
- He is a member of the PE Committee.
- He has a mother, father, and 2 older sisters.
- He dislikes (or is bad at) staying still.
- His favourite type of girl is someone who is not hypocritical.
- He spends his free time skateboarding at a park around his neighbourhood.
- He started playing basketball after being invited by his friend to play a mini-basketball game.
- His best basketball play is Lightning Dribble.
- The player he has his eye on is Izuki.
- His snaggle-like tooth may be a reference to the fact that he possesses animal instincts.
- Hayama is the only person who has laughed at Izuki's puns so far.
- He is quite agile since he somersaulted right over Kagami (who was coming up the stairs) without breaking his stride. 
- Hayama's version of a double clutch is a combination of a baseline reverse layup and a switch of hands, which is another two great signature moves of Michael Jordan, which he still could do in his second comeback for Washington Wizards.
- Hayama always has to “get in on the action” whenever someone is taking a picture. 
- Hayama wants to play Kise to find out if he can copy his moves. 
- Kuroko no Basuke chapter 177, page 13
- Kuroko no Basuke chapter 174, page 7
- Kuroko no Basuke chapter 175, page 15
- Kuroko no Basuke chapter 176, page 18
- Kuroko no Basuke chapter 177, page 14
- Kuroko no Basuke chapter 179, page 15
- Kuroko no Basuke chapter 181, page 16
- Kuroko no Basuke chapter 181, page 20
- Kuroko no Basuke chapter 183, page 1
- Kuroko no Basuke chapter 232, page 19
- Kuroko no Basuke chapter 177, page 7
- Kuroko no Basuke chapter 236, page 4
- Kuroko no Basuke chapter 176, page 19
- Kuroko no Basuke chapter 177, page 9
- Kuroko no Basuke chapter 196, page 2
- Kuroko no Basuke chapter 174, page 7, Season 3 Episode 5
- MICHAEL JORDAN- Wizards Double Clutch Reverse Layup
- Kuroko no Basuke Special CD Vol. 30 Track 7
- Kuroko no Basuke Special CD Vol. 30 Track 7
|Players||Seijūrō Akashi • Reo Mibuchi • Kotarō Hayama • Eikichi Nebuya|
|Former players||Chihiro Mayuzumi|
|Staff||Eiji Shirogane (head coach) • Takuo Satō (assistant head coach) • Shōta Higuchi (manager)|
|Teppei Kiyoshi • Makoto Hanamiya • Reo Mibuchi • Kotarō Hayama • Eikichi Nebuya|