Jinchūriki

The, or hosts, exhibit extraordinary powers, and in some cases are stronger than their Tailed Beasts for the very fact that they are able to control their power.

In addition, if a Tailed Beast goes too long without a host, it can lose its intelligence and become nothing more than a giant animal.

Appearance
Most of the Tailed Beasts have a visual effect on their respective Jinchūriki, which range from tattoo-like markings to physical or facial features. These are not present by the choice of the hosts, but manifest themselves due to the presence of the Tailed Beasts within them.


 * Gaara shows dark tanuki-like rings around his eyes similar to the those of the One-Tailed Shukaku. It is odd to note that even after Shukaku was removed from Gaara, the eye markings remained. This may be a result of Gaara's insomnia as Gamabunta pointed out.


 * Yugito Nii's eyes are thin and slanted in a cat-like appearance, possibly because of the Two-Tailed Monster Cat.


 * The Three-Tails Jinchūriki has an odd stitch pattern running down from his left eye to his jawline. The Three-Tailed Giant Turtle is shown only having this eye open, with a dark red patch around it. Strangely, this host is physically the shortest of all the nine Jinchūriki.


 * Rōshi has an odd tattoo or plate running from cheek to cheek and across his nose. It is not known if this is of his own design, or an effect of the Four-Tails.


 * The Five-Tails Jinchūriki's large stature could be due to the Five-Tails. He is covered from head to toe in red armor (only revealing the upper-half of his face), somewhat resembling muscle tissue. He is also shown to have a smokestack-like addition to his armor which lets out smoke or steam, possibly alluding to another effect of containing the beast.


 * The Six-Tails Jinchūriki is shown having very thin eyes. He is also shown blowing bubbles from a flute-like instrument, as well as having a bamboo container at his waist. It is not yet known if these are related to the Six-Tails.


 * The Seven-Tails Jinchūriki seems to have no outward markings. The only unusual characteristic she exhibits are her orange, pupil-less eyes and light green hair.


 * Kirābī has a tattoo on his left cheek resembling bull horns. This is ironic considering the Eight-Tailed Giant Ox is shown missing its left horn.


 * Naruto Uzumaki's Jinchūriki markings are some of the most noticeable. His markings consist of six markings on his cheeks that resemble whiskers. These are no-doubt due to the Nine-Tailed Demon Fox's presence inside him.

Personality
When the Tailed Beasts becomes infused with their hosts, their traits and influences can affect the hosts' personalities. According to the Akatsuki, the Jinchūriki tend to be lonely people who loathe humanity, which was proven true when the first two Tailed Beasts that were sealed by the organization was done with almost little response from their ninja villages. In fact, they were glad to be rid of their Jinchūriki. The Tailed Beasts are also very protective of their hosts for the sole reason: if the host dies, so does the demon inside. Likewise, if the Tailed Beast is removed from the host, the host would die.

Effects on Mental Health
There is a theory that all Jinchūriki have some sort of effect on their mental well being. This stems from the known fact that Gaara was unable to sleep ever. In the Chunin Exam arc, Gaara used the Feigning Sleep Technique to allow Shukaku to take control, and it was explained that he was unable to ever sleep normally because of Shukaku. This leads to the idea that all Jinchūriki have some kind of mental problem due to the fact that part of them is always fighting to keep their demon contained. For Gaara, this is manifest in the inability to sleep. Very little is known about most Jinchūriki. However, since Gaara's seal was weaker on purpose, it probably does not have that much of a heavy effect.

Sealing
So far, there are only two known methods to seal a Tailed Beast into a host. One was the Dead Demon Consuming Seal, which Minato Namikaze, the Fourth Hokage, used to seal the demon fox within Naruto; and the technique that Chiyo used to seal Shukaku within Gaara. The only known technique to extract a Tailed Beast is the Akatsuki's Illusionary Dragon Nine Consuming Seals, a three-day-long jutsu that with the combined effort of all the Akatsuki members, forces the Tailed Beast out of its host and into a nine-eyed statue. The Akatsuki has so far captured and sealed the first seven Tailed Beasts.

Power
So far, all Jinchūriki have displayed enormous powers and abilities, though each ability depends on which beast they have sealed within them. All Jinchūriki so far have different fighting styles (i.e. Gaara controls sand, Yugito controls fire, and Rōshi controls lava). It is also implied that Jinchūriki that have full mastery over their Tailed Beasts can actually create and, in a sense, become the Tailed Beast. This has been shown in different versions by the four Jinchūriki so far, however, Kirābī is the only one who can do this without a "catch" or condition (i.e. Gaara could create the full Shukaku body, but couldn't access all its abilities without losing control; Yugito could create and control the body of the demon cat, but only in miniature form; and Naruto could only create a shell of the demon fox with its chakra, but resembles his actual beast in very little ways and Naruto can also lose his mind in the process if he reaches his four-tailed state). However, it should be noted that Kirābī experiences a detrimental effect similar to the case of Naruto's four-tailed form. That is, Kirābī's skin also peels off as a result of the oppressive chakra.

Other than that Gaara is protected at all times by the Shield of Sand, regardless of his will (even self-inflicted injuries are prevented by the sand) and Naruto's body is capable of regenerate at a high extend of fatal injuries.

Known Jinchūriki

 * Gaara
 * Beast: One-Tailed Shukaku
 * Status: Captured and Extracted, later Resurrected


 * Yugito Nii
 * Beast: Two-Tailed Monster Cat
 * Status: Captured and Extracted


 * Unnamed Kirigakure Jinchūriki
 * Beast: Three-Tailed Giant Turtle
 * Status: Extracted under unknown circumstances, later Captured


 * Rōshi
 * Beast: Four-Tailed Beast
 * Status: Captured and Extracted


 * Unnamed Iwagakure Jinchūriki
 * Beast: Five-Tailed Beast
 * Status: Captured and Extracted


 * Unnamed Jinchūriki
 * Beast: Six-Tailed Beast
 * Status: Captured and Extracted


 * Unnamed Takigakure Jinchūriki
 * Beast: Seven-Tailed Beast
 * Status: Captured and Extracted


 * Kirābī
 * Beast: Eight-Tailed Giant Ox
 * Status: Active


 * Naruto Uzumaki
 * Beast: Nine-Tailed Demon Fox
 * Status: Active


 * Sora (Pseudo-Jinchūriki; Anime only)
 * Beast: Nine-Tailed Demon Fox's chakra
 * Status: Inactive (chakra absorbed by Naruto)

Trivia

 * Naruto is the only known Jinchūriki to not have fully transformed (it is possible that the others have fully transformed, but this remains unconfirmed). But he has almost completed his full transformation but was stopped by Minato Namikaze.
 * Naruto and Kirābī are the only two Jinchūriki remaining alive (Gaara had his life restored by Chiyo, but no longer has Shukaku).
 * Three of the known Jinchūriki (Naruto, Gaara, and Kirābī) each have some relation to a Kage (Naruto is the son of the Fourth Hokage, Gaara is the son of the Fourth Kazekage and is the Fifth Kazekage, and Kirābī is the brother of the current Raikage).