Jaken

was an imp who was extremely loyal to Sesshōmaru, often praising his master's greatness. Although Jaken was not nearly as powerful as his employer, he was skilled at wielding the Nintōjō. He seldom engaged in battle and was actually killed by Kaijinbō with Tōkijin, but Sesshōmaru resurrected him with Tenseiga.

In the Beginning
Upon becoming Sesshōmaru's servant, Jaken learned his master planned to create his own empire; he would become Chief Minister when the empire was established.

Jaken used the Staff of Two Heads to find the grave of Inuyasha and Sesshōmaru's father. However, they were only being led on a wild goose chase since the Black Pearl existed in Inuyasha's right eye. Using the Mu-on'na, Jaken tried to probe Inuyasha's heart for information, only to get a vague mention of the pearl. He was given a sound beating by Kagome before being hit by with Staff of Two Heads into a pond in a fashion similar to golf. Retrieving the staff after Sesshōmaru's acquired the Black Pearl, Jaken followed his master to the Border of the Afterlife, where the sword Tessaiga lay; however, a barrier prevented Sesshōmaru from wielding it. Inuyasha was immune to the barrier and successfully gained the sword (although it was Kagome who was able to draw it, not Inuyasha). During the fight, Sesshōmaru lost his left arm.

Jaken searched for him after returning to the world of the living, finding him in the forest near Asano Castle.

Sesshōmaru was then approached by Naraku, who offered help in stealing Tessaiga by giving Sesshōmaru a human arm with a shard of the Sacred Jewel embedded in it, which would allow him to wield the sword. Jaken was correctly mistrustful of the half-demon, as the plan backfired, and Sesshōmaru nearly got eaten by flames coming from the arm. Both of them found Naraku more troublesome than Inuyasha.

Jaken later came to Tōtōsai's home to remind him of the deadline he had set for the forging of a sword more powerful than Tessaiga. Informing Sesshōmaru that Tōtōsai had fled, Jaken accidentally insulted his master, believing his life had been shortened by 100 years. When Sesshōmaru fought Inuyasha and was defeated, Jaken questioned him about the Tenseiga, which Sesshōmaru immediately hit him with to prove it cannot cut. He then watched as his master took a dragon's claw as a temporary arm to defeat Tessaiga. When Sesshōmaru didn't return, Jaken went searching, thinking his only purpose was to be a test subject for Tenseiga. He later was shocked to find Sesshōmaru had revived a human girl named Rin.

Much to his annoyance, Jaken found Rin accompanying them. When Sesshōmaru commissioned Kaijinbō to create the Tōkijin from the fangs of the demon Goshinki, Jaken was cut in half and killed by the possessed swordsmith; Sesshōmaru later revived him with Tenseiga. While Sesshōmaru went to get his sword, Jaken kept an eye on Rin, meeting Kagura the Wind Sorceress for the first time.

When the Panther Demons attempted to gain revenge on Sesshōmaru and Inuyasha for what their father had done to their leader, Jaken watched in amazement as Inuyasha destroyed the barrier that their leader had erected.

Later forced to go with Rin to search for food, Jaken thought it was terrifying to let Inuyasha continue to have possession of Tessaiga, deciding to take the blade for his master. Trying to use a demon born of human regrets, the No-man, Jaken found the demon too stupid to carry out his plans. He instead tried to pose as a sharpener; the plan backfired, as everyone in Inuyasha's group but Inuyasha partook of his services. Worked to exhaustion, Jaken decided to use his final plan: create a hot spring. When Inuyasha bathed in the spring, Jaken attempted to take Tessaiga, but was burnt by the barrier; he decided to use the Robe of the Fire Rat to carry the sword with him. However, Rin's arrival tipped off Inuyasha to his plan. Although Jaken ordered RIn to give the Tessaiga to Sesshōmaru, she saved him instead and left the sword behind.

While stealing food, Jaken thought about Rin's words to him as Kagura arrived and kidnapped Rin. Returning to Sesshōmaru, Jaken informed him what happened, and Naraku extended an invitation to his castle in exchange for Rin, who was under his protection outside the poisonous atmosphere of the castle. Arriving at the castle, Jaken watched as Naraku transformed into a monstrous form and tried to absorb Sesshōmaru. When Naraku was forced to flee, both Jaken and Sesshōmaru realized Rin was kidnapped to be used as a means to buy time for escaping. Inuyasha forced him to explain what connection Rin had to Sesshōmaru.

Jaken later got poisoned by Saimyōshō, and begged Rin to find the plant that could cure him, as he would die at sundown if he didn't receive the antidote. Sesshōmaru returned with Rin and the plant, saving Jaken's life.

Mount Hakurei
Arriving at the sacred mountain, Jaken became ill from the barrier's effects, along with A-Un, but found Sesshōmaru was unaffected by the purifying powers of the barrier. Jaken tried his best to defend Rin from Suikotsu of the Band of Seven, but failed, as both were washed away by a river. After Rin's rescue, Jaken watched as Mount Hakurei's barrier collapsed, leading to the release of countless demons, copious amounts of miasma, and Naraku's demonic aura.

When Naraku emerged from the mountain, Jaken discovered that the half-demon had become arrogant, addressing Sesshōmaru without any honorifics. He then watched Naraku get torn to shreds by Tōkijin, only to see the force of the blast returned to Sesshōmaru, who reflected it and destroyed Naraku's head. However, Naraku didn't die, and continued to run away.

The Search Resumes
Kagura arrived again, making Jaken think she was after Rin once more; Jaken stood in front of the girl to defend her. However, Kagura denied having any memory of kidnapping her in the first place, and wondered if Sesshōmaru was around. Jaken yelled that Sesshōmaru would cut her head off if he was with them, the wind sorceress left after agreeing. This confused Jaken.

Later, arriving at the scene of Tekkei's decapitation, Jaken was surprised Sesshōmaru took Kagura's bait about Naraku being in the Border of the Afterlife where Tessaiga had been hidden. He followed his master into the battle for the final Sacred Jewel shard, but realized Sesshōmaru was so focused on killing Naraku that he was willing to let everyone die from the miasma. However, Kagome purified the poison and Naraku fled back to the world of the living.

When Sesshōmaru left to search the area, Jaken found himself once more babysitting Rin. He explained Sesshōmaru's plans for an empire and pointed out that the amount of time it would take to build it would be beyond Rin's human life-span. However, while Rin was upset, Ongokuki kidnapped her, forcing Jaken to look for her. Upon running into Sesshōmaru, Jaken informed him of what happened; he was then forced to look for both Rin and Sesshōmaru. He then ran into Inuyasha's group (but not Inuyasha himself, as it was the night of the new moon), informing them of what happened. By daybreak, Jaken was tired, but eventually found both Rin and Sesshōmaru. When Sesshōmaru said he was continuing his search for Naraku, Jaken asked if he could come along, only for Rin to say "do you need to ask?"

When Kagura flew by them and landed in a river, Jaken told Rin not to rescue her; however, he was ignored and ended up getting caught in the river with both of them. After Sesshōmaru rescued them and gave Jaken a whack to the head as punishment, Kagura was discovered to have a hole straight through her chest. To their amazement, the wound sealed itself and she came back to life. Kagura gifted them with shards of demonic energy to find Naraku's heart, which held the Fuyōheki to hide it. When Jaken questioned her about using Sesshōmaru to kill Naraku, Jaken was shocked that hearing her flattered Sesshōmaru. Upon Kagura's departure, Jaken dismissed Rin's idea that Kagura loved Sesshōmaru.

They later arrive at Goryōmaru's grave, only to find it empty and several demon corpses littering the temple.

The Final Act
During the events of The Final Act, Jaken was burdened with several additional tasks: looking after the crystals Kagura left them, and protecting Kohaku as well as Rin, after Sesshōmaru saved Kohaku from Byakuya. When they went to visit Sesshōmaru's mother at her castle, Jaken noted that her icy, indifferent personality was exactly the same as her son's; he was also annoyed that she kept refusing to remember his name. When he learned that Rin could not be saved, he burst into tears, although he claimed part of it was that he was shedding tears on behalf of Sesshōmaru, but he was relieved when she was resurrected.

Jaken later witnessed Sesshōmaru's battle with Magatsuhi; initially he feared that his master had been killed and tried to comfort Rin, only to witness Sesshōmaru obliterate Magatsuhi's body with his new sword, the Bakusaiga. When Jaken stated he had known all along that Sesshōmaru would emerge victorious, Shippō mocked his earlier words. To shut him up, Jaken quickly used the Nintōjō to set Shippō's tail on fire.

After returning to Kaede's village and setting off in pursuit of Magatsuhi and Naraku for the final battle, Sesshōmaru said that Jaken needed to stay behind with Rin, as it was too dangerous for either of them. For once wanting to follow his master into battle despite his cowardice, Jaken obeyed with great reluctance. However, he became alarmed when Rin was possessed by a fragment of Magatsuhi's spirit; while she and Jaken were walking in the woods Naraku possessed her and kidnapped her. Jaken was terrified of Sesshōmaru's reaction, but his master ignored him and went straight after Naraku.

Eventually, Shippō, Kohaku, and Jaken were the only ones left behind at the village. When Shippō and Jaken began mocking each other's unwillingness to join the battle, Kohaku indicated they could ride A-Un up to Naraku's body. However, once they entered it, all three were rapidly separated. Jaken became hopelessly lost inside Naraku until a wall exploded open and Sesshōmaru came flying through it. Delighted, Jaken leaped towards his master, only to get his face stepped on.

Three years after Naraku's demise, Jaken was shown to still be traveling with Sesshōmaru.

Personality
He was smaller than Rin and his physical strength and demon power were weak. It was clearly shown that he was capable of fighting to some degree when he torched the warriors upon Sesshōmaru's orders, but he often let down his guard when he became proud, arrogant, or close minded. Classic examples of this were the times when Kagome was able to take him down by throwing a few skulls or stones.

Jaken had the staff of Two Heads, which bore the faces of a woman and an old man, and had a function of detection. The staff could also serve as a weapon, as the old man's face could spew huge blasts of flame that were powerful enough to annihilate many enemies in an instant; although, as shown, this was usually only effective against human soldiers or minor demons.

Eternally loyal to Sesshōmaru, he was sometimes disappointed with compliments that had no meaning and odd jobs that offer no reward, but he was proud of Sesshōmaru and puts his heart into everything in order to do his best. He was not entirely willing to take care of Rin, but he showed his loyalty to Sesshōmaru and put his life on the line to obey his master's orders. Jaken was surprisingly knowledgeable on many subjects, but his inability to explain them in a non-arrogant or insulting manner meant that few took him seriously.

Physical description
Jaken was a very small green-skinned demon. He had a big mouth for one so small, and large yellow eyes that took up almost half his face. His mouth was similar to a bird's beak, and his ears were traditionally pointy. He wore a simple brown top and light-brown pants. He wore no shoes, and had a small black hat upon his head. His hat was tied in place with a white strap going under his chin.

Abilities
Jaken had few established demonic abilities except for his heightened senses, his projected demonic aura (which was extremely weak, as shown when the barrier at Mt. Hakurei began affecting him rapidly), his ability to sense other demon auras, and greater resistance to cold temperatures. However, he had some skill with the Nintōjō, being able to use it as a detector and a rather effective flamethrower (on one occasion, he also used it to conjure a hot spring whose fumes paralyzed the unsuspecting Inuyasha). Like many demons with human-level intelligence, Jaken aged extremely slowly; he was at least 150 years old at the start of the series, and could live at least another two centuries.

Relationships
Despite often reflecting that his service to Sesshōmaru had not led to much improvement (and indeed, often put him in dangerous or terrifying situations), Jaken, in fact, had chosen to follow Sesshōmaru of his own free will, after Sesshōmaru (inadvertently) saved his life, and the fact that he admired Sesshōmaru's power and good looks. To the point of being a sycophant (a suck-up), Jaken respected Sesshōmaru, and always praised Sesshōmaru whenever he defeated a demon, much to Sesshōmaru's annoyance. To Jaken's credit, unlike Myōga (who immediately abandoned Inuyasha in any dangerous situation), Jaken was completely loyal to his master, even if his usefulness was minimal; he always stuck by Sesshōmaru's side even in times of danger (except on one occasion, where he tried to back out by bidding Sesshōmaru 'good luck' and got whacked on the head). The best example of this was when Sesshōmaru went after the incredibly dangerous demon Magatsuhi, leaving Jaken behind for his own safety; Jaken burst into tears, pleading to be allowed to follow Sesshōmaru into battle. He understood Sesshōmaru better than most; however, at times, he was far too verbal about his knowledge of Sesshōmaru's personality, and was punished for it by getting a bump on the head or being stepped on. Jaken only became openly angry at Sesshōmaru on one occasion, and Sesshōmaru's passive/aggressive response immediately scared him back into line. Sesshōmaru had never followed through on his regular threats to kill Jaken (either for failing to accomplish a task - such as looking after Rin - or for talking too much). In fact, Sesshōmaru resurrected him with Tenseiga after Jaken was killed by Kaijinbō - an action that seemed contradictory to Sesshōmaru's cold, unfeeling personality, especially as he had other priorities at the time. From this, it can be assumed that Sesshōmaru had at least the bare minimum of concern for Jaken.
 * Sesshōmaru

At times, Jaken sometimes wept or showed sadness for Sesshōmaru. It it unknown whether it was for Sesshōmaru's sake (for he may have an inability to express emotions) or if it was for his own. Examples include when Jaken cried because of Sesshōmaru's "inability to cry" or when Jaken sneezed instead of Sesshōmaru when Inuyasha and his companions were talking about him, due to a common Japanese superstition that one sneezes when gossiped about. Despite always being under extreme stress merely trying to avoid angering his master, Jaken took pride in his somewhat lowly position as Sesshōmaru's 'vassal', although he aspired to become a prominent minister within the 'empire' he believed Sesshōmaru would establish one day. Three years after Naraku's death, Jaken was shown to still be traveling with his master, as sycophantic as ever.

At first Jaken disliked Rin as she was a human. However, as time went by, he began to treat her slightly better, mostly because he was often forced to act as her guard while Sesshōmaru was elsewhere. Jaken sometimes acted as if he hated her, mostly because Sesshōmaru treated her more favorably, but in truth, he didn't want Rin to get hurt. Whenever there was trouble, Jaken always told Sesshōmaru he would guard her or begged him to save her. He also worried if Rin got hurt that Sesshōmaru would kill him; often, when Rin disappeared, Jaken frequently hid from Sesshōmaru's perceived wrath. Rin often liked to make up songs such as "Jaken-sama, Jaken-sama, why are you green?", and poked fun at the fact that he was half her size (antics which understandably get on Jaken's nerves). When Rin died in the netherworld, Jaken was shown shedding tears. Whether they were just for Sesshōmaru's sake is unclear, but given that he discovered that Rin was going to die before Sesshōmaru did, he clearly underwent some grief in response to her death, and, in turn, was happy when she was revived again. On at least one occasion, Rin and Jaken were shown having fun together, such as when she taught him how to catch fish with his hands. Although very aware of Jaken's personality flaws, mainly arrogance and an inability to shut up, Rin clearly respected and cared about Jaken to some degree, since she referred to him as 'Master Jaken' and went to great lengths to get him an antidote when he was poisoned.
 * Rin

Jaken and Inuyasha had a very bitter relationship. Despite the number of times Inuyasha had saved him, Jaken always turned against him due to the perpetual conflict between Inuyasha and Sesshōmaru. Inuyasha also seemed to bully him, much like the equally small fox demon Shippō. For example, when Jaken started to scold him about Inuyasha calling him "small", the hanyō grabbed him and tried to stretch him out until Kagome told him to "sit". However, this wasn't much help as Inuyasha landed on top of Jaken.
 * Inuyasha

Jaken hated Miroku almost as much as Inuyasha, mostly because of their first encounter; Jaken was almost drawn into Miroku's Kazaana, and when the poisoned Miroku attempted to get information from him regarding the Saimyōshō, Jaken insulted him. Miroku then beat him to a pulp despite being full of poison. In all following encounters, Jaken always did his best to steer clear of Miroku.
 * Miroku

Jaken felt some sympathy for the young fox demon, as both were small in size and were bullied by Inuyasha. However, while Jaken tried to be civil towards Shippō, the fox demon often made remarks that annoyed him, such as references to his height and large ego.
 * Shippō

Manga vs. Anime
The manga explained little about Jaken's past, but the anime showed that Jaken was once a lord among similar demons (episode 79, "Jaken's Plan to Steal Tessaiga"). During battle with another yōkai tribe, the enemy leader had Jaken by his neck when Sesshōmaru appeared and told the demon to move out of his path. When the enemy leader did not comply, he calmly destroyed the yōkai with his poison whip. Out of a sense of obligation, Jaken followed Sesshōmaru, who allowed him to become his servant if he could wield the Staff of Two Heads.

Trivia

 * There is some inconsistency in Jaken's recollection of how long he has been serving Sesshōmaru. In "Jaken's Plan to Steal the Tetsusaiga," Jaken said that he had been serving Sesshōmaru for "several decades," but in "Sesshomaru and Koga: A Dangerous Encounter," he said that it had been "centuries." It is possible that in the latter case, Jaken simply exaggerated the amount of years he had been in Sesshōmaru's service in order to make his record seem more impressive to Ginta and Hakkaku. It is known, however, that Jaken had been with Sesshōmaru for at least 50 years at the time of Inuyasha's awakening, as he was by his master's side when the Panther Demon Tribe attacked Japan shortly after Inuyasha was sealed to a tree by Kikyō.