The Tailed Beasts.

The tailed beasts (尾獣, bijū) are the nine titanic behemoths within the Naruto series. They are differentiated by the number of tails they have, ranging from one to nine. The tailed beasts are living forms of chakra, sometimes referred to as "Chakra Monsters" (チャクラのバケモノ, Chakura no Bakemono), giving them immense reserves of especially strong chakra that far outmatches most shinobi. The tailed beasts' chakra is coloured red.

They also have the ability to communicate telepathically with each other and their jinchūriki, and possess several levels of consciousness. There is the initial level where the beast may appear in a habitat of sorts seemingly imprisoned in some way by whatever fūinjutsu that sealed them. The second level is where all the tailed beasts can convene, free of any restrictions and communicate with one another. The jinchūriki are also able to enter there, but in order to do so, they must be completely linked with their tailed beasts.

The tailed beasts are also able to freely transfer their chakra to whomever they choose.



      Shukaku (守鶴, Shukaku), more commonly known as the One-Tail (一尾, Ichibi), is one of the nine tailed beasts. * Hasme
Shukaku is characterised as a wild and short-tempered individual, and often speaks in a bombastic and incoherent manner, giving it the demeanour of a drunken madman. Shukaku holds great confidence in its own abilities, especially its absolute defence.[19] According to Gaara, prior to its introduction, Shukaku relishes the opportunity to kill anyone in sight, even more so during a full moon. Like all tailed beasts, Shukaku has shown a strong desire to preserve its own life, to which it will grant its jinchūriki the power to control sand as well as allowing them to transform into it in a state of need and blood-lust.

Shukaku harbours a bitter grudge towards Kurama, in response to its beliefs that the tailed beasts' strength is measured by the number of tails and, as such, views Shukaku as the weakest. Due to this, Shukaku will find any opportunity to surpass its arrogant rival. Its hatred towards humans led it to spark fear in Gaara, reminding him that if he goes into a deep sleep, the tanuki will possess his body and murder all humans. This resulted in Gaara's developing insomnia. Shukaku had a similar attitude towards Bunpuku, but its jinchūriki learned to live with it and eventually, Shukaku complimented him by comparing him to the Sage of the Six Paths.


     Matatabi (又旅, Matatabi), more commonly known as the Two-Tails (ニ尾, Nibi), is one of the nine tailed beasts. *Degan

Compared to most of the tailed beasts, Matatabi has shown to be respectful and polite towards others, speaking in a formal manner using "watashi" (私) when referring to itself and using honourifics when addressing its jinjuriki
 
   Isobu (磯撫, Isobu), more commonly known as the Three-Tails (三尾, Sanbi), is one of the nine tailed beasts.

Isobu speaks in a timid manner, referring to itself as "boku" (ボク) which is usually used by young boys.

 Son Gokū(孫悟空, Son Gokū), more commonly known as the Four-Tails (四尾, Yonbi), is one of the nine tailed beasts.

Son Gokū is a very prideful tailed beast, as it detests being called by the name "Four-Tails" and boasts about its lineage.

It also hated humans, due to the fact that humans had enslaved it, and believes that apes are more intelligent than humans. However, when talking about the Sage of the Six Paths, it showed him great respect. It also seems to have taken a liking to Naruto Uzumaki, as it was moved by his actions for truly trying to save it from being controlled by Tobi and even gave him some of its chakra before being sealed away. He also treats his fellow tailed beasts with much respect, as he addresses them by their name, as seen with Kurama. Son also has a high amount of respect for those who respect the tailed beasts.

 Kokuō (穆王, Kokuō), more commonly known as the Five-Tails (五尾, Gobi), is one of the nine tailed beasts. *Katokari

Kokuō seems to be a quiet and reserved individual. Though it does not speak much, Kokuō uses the rather old-fashioned "watakushi" (私) when referring to itself, causing it to come across as very polite. It also has pride as a tailed beast, being dismayed at being controlled and being used as Tobi's puppet during the Fourth Shinobi World War. After the end of the war, Kokuō declared that it wants to seclude itself in the forest, which implies it is a pacifistic individual, not wanting confrontations anymore.

Saiken (犀犬, Saiken), more commonly known as the Six-Tails (六尾, Rokubi), is one of the nine tailed beasts.

Though much has not been seen of Saiken's personality, the giant slug uses "ore" (オレ) when referring to itself, "ore" being a boastful way of saying "I". It also speaks with a dialect which may possibly be Ōsakaben in origin. In the anime, Saiken also seemed to be kinder and not as self-serving and malicious as most other tailed beasts, as when Utakata asked for its help to save Hotaru it seemed to willingly comply; and later it simply receded back into Utakata without trying to take him over. However it was not above killing for self preservation, as seen when it killed Harusame when he attempted to extract it from its jinchūriki. In the anime, it speaks with a high pitched voice and appears to be very energetic.

Chōmei (重明, Chōmei), more commonly known as the Seven-Tails (七尾, Nanabi), is one of the nine tailed beasts.  *  Otori. Shirakawa

Chōmei seems to have a happy, go-lucky personality — which it seemingly shares with its jinchūriki as shown when it introduced itself to Naruto, referring to itself as "Lucky Seven Chōmei" (ラッキーセブン重明, Rakkī sebun Chōmei) which might be an allusion to the fact that it has seven tails and the number seven having long been seen as a lucky as well as happy number. It also had a habit of using lucky in conversation, reflecting its personality.

 Gyūki (牛鬼, Gyūki), more commonly known as the Eight-Tails (八尾, Hachibi), is one of the nine tailed beasts.

Gyūki is characterised as a tough and serious individual.  Gyūki was also shown to have a good analytical ability, as it told Killer B that if he left Ponta and Sabu and ran away from them, Kisame and his water dome would follow him and they (Sabu and Ponta) would be freed. With regards to its relationship with the other tailed beasts, Gyūki mentioned that it and its brethren disliked Kurama for its habit of ranking their strength based on their number of tails. However, it insisted that was no reason for not helping Naruto to control Kurama's power, hinting a benevolent side. Since then, both Gyūki and B have taken a liking to Naruto.

In the past, Gyūki was infamous in Kumo for being wild and violent, as it went on countless rampages whenever its former jinchūriki would lose control of it. This was most likely due to its hatred against humans for oppressing and sealing it away many times. Gyūki maintained this behavior until it was sealed within B, who would later change it after he bested it in one-on-one combat. Since then, Gyūki's personality has become much more relaxed, becoming close friends with B; even allowing him to sit on top of its muzzle while talking to it leisurely. However, B tends to annoy Gyūki to comical effect, as its no-nonsense demeanour often contrasts with B's tendency to goof off whenever he likes, adding fuel to Gyūki's irritation to its vessel.

As a result, Gyūki is not above bad-mouthing B and is also known to reprimand him in serious occasions. This was seen when Gyūki criticised B for rapping in his fight with Kisame when he should have been completely focused on their opponent, and later when it comically bumped B in the head when the latter started to mention in a perverted manner how Yugito's chakra receivers were embedded in her left breast. Because of this, Gyūki appears to be much more noteworthy than B as far as responsibility is concerned. Nonetheless, Gyūki formed a very strong bond with B, as even after being extracted from its jinchūriki, the tailed beast severed a piece of itself to help sustain B's life. Following its release from Kaguya, Gyūki expressed a desire to return to B, noting it had gotten used to his awful rapping and felt odd not hearing it.

Gyūki's relationship with its B's predecessor Blue B was unknown in the manga, other than the fact it would pounce on the "hole" in Blue B's heart and assume control over him. In the anime, however, Gyūki stated it had high hopes for Blue B, indicating it bore no ill will towards its former host.

Kurama (九喇嘛, Kurama), more commonly known as the Nine-Tails (九尾, Kyūbi), is one of the nine tailed beasts

Kurama is a cynical and shrewd individual, along with a somewhat twisted sense of humour. It uses "washi" (ワシ) when referring to itself, which is generally used by older men. Kurama is also very prideful, as it believes that a tailed beast's strength is determined by its number of tails, which earned the fox nothing but disapproval from its brethren, especially Shukaku. Despite its arrogance, Kurama acknowledges the fact that it alone doesn't stand a chance against the Ten-Tails, and eventually learns not to underestimate its opponents   However, it does easily get annoyed when its jinjuriki uses a power other than its own, claiming its jinchūriki needs no other power than its own. It is also shown that Kurama deeply cares about the Sage of the Six Paths, viewing him with great respect and even shed tears after the Sage had imparted his final words to them.

Naruto and Kurama fist bump
The change in dynamics between Naruto and Kurama.
Long years of receiving humanity's negative treatment caused Kurama to develop intense hostility and distrust against them, even going as far as proclaiming itself to be the living embodiment of hatred. Ever since its sealing within Naruto, Kurama plotted to use the young shinobi's dependence on its power to gain control over him and break free from the seal, before it was bested in combat and stripped of most of its chakra. However, Kurama's attitude towards Naruto soon began to change during the Fourth Shinobi World War, when the young shinobi told the fox that he hoped to resolve its hatred someday. Despite Kurama reproaching him for making such a claim, the fox nevertheless had developed a level of respect for Naruto and his determination. It even noted that Naruto was different from the humans it had previously encountered, eventually allowing its jinchūriki to utilise the Nine-Tails Chakra Mode without consequence. Later, as Naruto told Son Gokū of his desire to save the tailed beasts and become friends with Kurama, the fox — having witnessed all of the challenges and endeavours Naruto had in his life — silently told the young shinobi that if he truly intended to help them, he would have to prove it through his actions. When Naruto successfully freed Son Gokū from Obito's control, Kurama finally became convinced of Naruto's word and offered to meld its chakra with his as a coalition, to which Naruto then removed the seal that restrained it and happily acknowledged the fox as his team-mate and a member of Konoha.

Within that short space of time, the two had begun to express trust in one another, even to the point where Naruto would allow Kurama to take control of his body without worry, and switch back without hesitation.[36] Kurama later admitted that it had the utmost faith in Naruto being able to defeat Obito and to carry on the legacy Minato and Jiraiya had left him, which also means that it no longer holds a grudge against Minato for sealing it inside of Naruto. Kurama is also shown to be more caring about its comrades now as it put itself in harm's way to save B and Gyūki and even expressed concern for Naruto managing so many chakra cloaks at once. Kurama is also shown to have a more comical side to it when it argued with Naruto about each other's stubbornness, and later when it nervously lashed out and flipped off a joyful Naruto after the tailed beasts were freed.