Jaken

""Splendid, my lord, splendid. Nothing less than I expected!""

- Jaken

was a kappa demon who is extremely loyal to Sesshōmaru, often praising his master's greatness.

Although Jaken is not nearly as powerful as his employer, he is skilled at wielding the Nintōjō (人頭杖, Staff of Two Heads). He seldom engages in battle and is actually killed by Kaijinbo with Tōkijin, but Sesshōmaru resurrects him with Tenseiga.

History
In the early part of the story, Jaken uses the Staff of Two Heads to find Inuyasha's and Sesshōmaru's father's grave. He eventually became not much more than comic relief, having hardly any role in the story.

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

Jaken has the staff of Two Heads,which bears the faces of a woman and an old man and has a function of detection The staff can also serve as a weapon as the old man's face can spew flame that is powerful enough to annihilate many enemies in an instant.

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

Abilities
Jaken has few established demonic abilities except for his heigtened senses, his projected demonic aura (which is extremely weak, as shown when the barrier at Mt. Hakirei began effecting him rapidly) and greater resistance to cold temperatures. However, he has some skill with the Nintojo, 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)

Relationships
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 Sesshomaru was elsewhere. Jaken sometime acts as if he hates her- mostly because Sesshomaru treats her more favorably- but in truth he doesn't want Rin to get hurt and whenever there's trouble, Jaken always tells Sesshōmaru he will guard her- or begs him to save her. He also worries if Rin gets hurt that Sesshōmaru will kill him; often, when Rin dissapears Jaken frequently hides from Sesshomaru's percieved wrath. Rin often likes to make up songs such as "Jaken-sama, Jaken-sama, why are you green?" and pokes fun at the fact that he is half her size (antics which understandably get on Jaken's nerves). When Rin dies in the netherworld, Jaken is shown shedding tears. Whether they are just for Sesshōmaru's sake, we don't know, but given that he discovered that Rin was going to die before Sesshomaru did, and wept in response, he clearly underwent some grief in response to Rin's death- and, in turn, was happy when she was revived again. On at least one occasion Rin and Jaken were shown having fun together as 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 respects and cares about Jaken to some degree, since she refers to him as 'Master Jaken' and went to great lengths to get him an antidote when he was poisoned.
 * Rin

Despite often reflecting that his service to Sesshomaru has not led to much improvement (and indeed, often puts him in dangerous or terrifying situations) Jaken in fact chose to follow Sesshomaru of his own free will, after Sesshomaru (inadvertently) saved his life; that and the fact that he admired Sesshomaru's power and good looks. To the point of being a sychophant (a suck-up), Jaken respects Sesshōmaru and always praises Sesshōmaru whenever he defeats a demon, much to Sesshōmaru's annoyance. To Jaken's credit, unlike Myoga, Jaken's loyalty to his master is total, even if his usefulness is minimal; he always sticks by Sesshōmaru's side even in times of danger (except one occasion where he tried to back out by bidding Sesshomaru 'good luck' and got whacked on the head). He understands Sesshōmaru better than most; however, at times he is far too verbal about his knowledge of Sesshomaru's personality, and is punished for it is by getting bump on the head or stepping on him. Jaken only became openly angry at Sesshomaru on one occasion, and Sesshomaru's passive/aggressive response immediately scared him back into line. Sesshomaru has 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, Sesshomaru resurrected him with Tenseiga after Jaken was killed by Kaijinbo- an action that seems contradictory to Sesshomaru's cold, unfeeling personality, especially as he had other priorities at the time. From this, we can presume that Sesshomaru had at least the bare minimum of concern for Jaken.
 * Sesshōmaru

At times, Jaken may sometimes weep or show sadness for Sesshōmaru. It is unknown whether it is for Sesshōmaru's sake (for he may have an inability to express emotions) or if it is for his own. Examples include when Jaken cries because of Sesshōmaru's "inability to cry" or when Jaken sneezes instead of Sesshōmaru when Inuyasha and his compantion were talking of him, a common Japanese superstition that one sneezes when gossiped about. Despite always being under extreme stress merely trying to avoid angering his master, Jaken takes pride in his somewhat lowly position as Sesshomaru's 'vassal', although he aspires to become a prominent minister within the 'empire' he believes Sesshomaru will establish beyond his father's kingdom. Three years after Naraku's death, Jaken is shown to still be traveling with his master, as syncophathic as ever.

Jaken and Inuyasha have a very bitter relationship. Despite the number of times Inuyasha has saved him, he always turns against him due to the conflict between Inuyasha and Sesshōmaru. Inuyasha also seems to bully him. As when Jaken started to scold him about Inuyasha calling Jaken "small", the hanyō grabbed him and tried to stretch him out until Kagome told him to "Sit". Jaken hates 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 Saimyosho, 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.
 * Inuyasha
 * Miroku

Manga vs. Anime
The manga explains little about Jaken's past, but the anime shows 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 this was not obeyed, he calmly destroyed the yōkai with his poison whip. Out of a sense of obligation, Jaken followed Sesshōmaru, who allowed him to become a servant if he could use the Staff of Two Heads.