AboutMight Guy is the extremely zealous leader of Team Guy, consisting of Rock Lee, Neji Hyuga, and Tenten. Known for his thick eyebrows, green jumpsuit, and shiny bowl haircut, Guy often refers to himself as "Konoha's Prideful Green Beast" (木ノ葉の気高き碧い猛獣, Konoha no Kedakai Aoi Mōjū?, aka. "Konoha's Noble Green Beast" wink . Guy's favorite foods are super-spicy curry rice and curry udon, though he finds it impossible to dislike food. His favorite phrase is "Bursting with youth!"
Guy is on good terms with all of his students, though seems to have a particular interest in Lee, who reminds Guy of himself when he was younger. As such, Guy puts much more interest in Lee's training than Neji's or Tenten's, continuing to train Lee long after the others have given up for the day. Because of this, and due to Lee's unyielding desire to master the art of taijutsu, Guy has taught Lee a number of dangerous and forbidden techniques, giving the stipulation that Lee can only use them under specific circumstances. Although Guy knows of the dangers that teaching the techniques to Lee entails, Guy wishes for Lee to be able to prove himself to be a splendid ninja, and as such turns a blind eye to the repercussions.
Guy specializes in using taijutsu, and is able to use many powerful taijutsu techniques. While he is capable of using ninjutsu and genjutsu, he tends to choose not to, even going so far as to use regular disguises instead of the Transformation Technique. In the few instances that he has used ninjutsu, it has always been offscreen, such as when he summoned Ninkame prior to his first appearance. Despite his apparent decision to only use taijutsu, Guy is a talented ninja, graduating from the Academy at age 7 and becoming a Chunin at age 11. Itachi Uchiha has on different occasions warned others against underestimating Guy. Given that Itachi and his accomplices are extremely dangerous ninja, such a warning is an indicator that Guy is an excellent combatant.
Guy believes that "hard work without believing in yourself is worthless", and as such trains by repeatedly jumping sideways and hitting mitts in an effort to better himself. Guy, and by extension Lee, lives his life by his own "My Rules" philosophy, which involves setting tougher goals for failure so something good comes of it. For example, he vowed to walk 500 laps around Konoha on his hands if he lost a contest with Kakashi, and proceeded to do so upon losing, even though people stopped paying attention eventually. Lee's willingness to train in the same manner as Guy seems to have caused him to surpass his master, as by the end of Part I Guy has difficulty keeping up with Lee.
Guy is the self-proclaimed rival of Kakashi Hatake. Kakashi, however, is indifferent to their rivalry, which annoys Guy to no end. Guy randomly challenges Kakashi to contests of skill, and has a acquired a record of 50 wins and 49 losses in doing so. Given that the contests that make up this figure are so varied (ranging from Rock, Paper, Scissors to sumo-wrestling), this it is not much of an achievement on Guy's part. Nevertheless, Guy is proud of his record. In his rivalry with Kakashi, Guy has developed an effective counter against Sharingan users: by focusing on their feet, Guy can both predict the movements of the enemy and negate the Sharingan's necessity of having eye-contact. Currently, Guy is the only ninja who can use this technique.
Guy has many mannerisms unique to him in the series that are meant to be seen as corny and old fashioned, a reference to common clichés of "youth" (青春, seishun?) anime. He is best known for his "nice guy pose", which consists of giving a thumbs up, winking, and smiling with teeth so white they give the proverbial "ping". This action is often used by both Guy and Lee to indicate commitment to a statement they had just made, their highest form of a promise. Guy's teacher-student relationship with Lee also carries distinct attributes, such as when Guy will punch Lee for a slight infraction of a rule. After Guy assigns Lee an arduous training task as punishment, meant to recapture Lee's focus and discipline, the two may then burst into tears and embrace, in brief regret for the strong blow Lee was given.
 Part I
 Chunin Exam arc
During the preliminary matches of the Chunin Exams, Guy takes the role of Lee's coach prior to his match with Gaara, giving him general advice on what to do. During the actual fight, Lee continually finds his fighting level to be inadequate in defeating Gaara, and each time Guy gives his consent for Lee to increase the strength of his attacks. When Lee begins to run out of options, Guy allows Lee to open the first five chakra gates in order to defeat Gaara. Although Lee does so, his efforts are unsuccessful and he is left heavily injured. When Gaara is about to kill Lee, Guy steps in to stop the match, not willing to allow anything to happen to Lee. As Lee is taken away to be healed, one of the medics informs Guy that the injuries to Lee's body are so severe that he will never be able to fight as a ninja again. Guy is crushed by this prospect, and regrets ever teaching Lee so many dangerous techniques.
A month later, Guy accompanies Lee in watching the final matches of the Chunin Exam. When the invasion of Konoha begins, Guy teams up with Kakashi in repelling the invading forces and protecting the unconscious spectators.
 Return of Itachi arc
As Kakashi lies on the verge of defeat in his battle with Akatsuki members Itachi Uchiha and Kisame Hoshigaki, Guy arrives in time to repel Kisame and save Kakashi. Itachi, recognizing Guy as a threat, orders Kisame to flee. After getting Kakashi some medical attention, Guy follows the two and tries to sneak attack them, though ends up kicking Jiraiya in the face instead. After apologizing for his mistake, Guy learns that Jiraiya is looking for the talented medical ninja Tsunade, and asks that Jiraiya be sure to find her in the hopes that she will be able to heal Lee.
 Sasuke Retrieval arc
Once Tsunade is found and returns to Konoha, she finds that the operation that will heal Lee has a 50% chance of death. Although Lee is reluctant to risk his life, Guy convinces Lee to go through with the operation, saying that all the work Lee has done means that he will definitely survive. In the event that Lee does die during the operation, Guy says that he will die too, as he has no point in living if he can't help Lee become a great ninja. Lee's operation is a success, and Guy visits him daily until he is ready to start training again.
 Anime filler arcs
During the course of the filler arcs, Guy is the only adult to receive a considerable amount of screen time. When Lee's dojo goes unchallenged in one arc, Guy challenges Lee himself disguised as stranger. Although the disguise is very bad, Lee never catches on that it is actually Guy. In The Third Great Beast arc, Guy begins training a visiting ninja named Yagura. When Yagura traps Guy and Lee within a castle and force them to fight equally skilled counterparts, Guy and Lee open the first five chakra gates to defeat their opponents and destroy the castle. Later, in the Konoha 11 arc, Guy leads Konoha's available Jonin to stop a suspected invasion by Takigakure, though in reality the Takigakure forces were just having a training exercise.
 Part II
 Rescue Gaara arc
Team Guy is assigned by Tsunade to assist Team 7 in rescuing Gaara. On their way to meet Team 7, Guy again encounters Kisame Hoshigaki, who wants revenge on Guy for hitting him during their last encounter. Guy, however, doesn't seem to remember Kisame, which greatly agitates the Akatsuki member. When Kisame succeeds in imprisoning Guy's teammates, Guy opens the sixth chakra gate and uses his Morning Peacock to defeat Kisame. As the group examines Kisame's corpse, they find that it was not Kisame, but merely a body double.
Upon reuniting with Team 7 and reaching the Akatsuki hideout, Team Guy is assigned to disable a barrier surrounding the hideout's entrance. Although they complete the task, they are forced to fight clones of themselves, though each member eventually succeeds in defeating their lookalikes. After Gaara is rescued, Guy carries Kakashi back to Konoha via a piggyback, the latter too exhausted to walk there under his own power. Their students are deeply disturbed by the sight, though Guy doesn't seem to notice and instead has a race with Lee to see who can reach Konoha first.