Hidan

is the foul-mouthed partner of Kakuzu and is the second newest member of Akatsuki at the time of his expulsion. Himself and his partner Kakuzu are both "immortal" which allows the two to function together in a team, despite thee fact that they fight with little regard to each other. The first kanji in Hidan's name (飛) stands for hisha, the rook in shogi

Background
Hidan belongs to the  religion, a religion that worships a deity named of the same name that commands slaughter,  and where anything less than utter destruction is considered a sin. The amulet around his neck is a symbol of Jashin and he uses it to pray to his god before battles. Before battles start Hidan prays to Jashin and asks for nothing short of a kill or, when he is not allowed to kill his opponents, for forgiveness. After battles, should he have time, Hidan performs a thirty-minute ritual in accordance with his religion that culminates by stabbing himself in the chest and lying upon the ground. . Hidan is very devout to his faith in that he wouldn't even fight Yugito Nii without praying beforehand. Despite his religious desires to kill, he has expressed a desire to die himself, but can't because of his immortality.

Hidan also isn't on good grounds with Pein. Hidan openly argues with him when he was ordered to retreat from a battle. When Kakuzu convinces him to retreat, he entertains the idea of asking Jashin to curse Pein.

Hunt for the Nine-Tails
Hidan and Kakuzu are first revealed after cornering Yugito Nii, host of the Two-Tailed Demon Cat in the sewers of Kumogakure. Even when Yugito transformed herself into the demon cat, the Akatsuki managed to defeat her, allowing Zetsu to take her off their hands. After Hidan completes his ritual, the duo continues to the Land of Fire to hunt down the Nine-Tailed Demon Fox.

Upon arriving in the Land of Fire, Hidan begrudgingly joins Kakuzu in attacking a temple so that they can collect the bounty on the head monk. The monk and his subordinates are defeated, and after Hidan finishes his ritual they take the monk's body to the nearest bounty station. Upon arriving, Hidan opts to stay outside, not liking that the bounty station is hidden inside a bathroom and as such smells like urine. While he waits for Kakuzu to collect the bounty, Hidan is attacked by Asuma Sarutobi, Izumo Kamizuki, Kotetsu Hagane, and Shikamaru Nara. Despite being immobilized, and stabed in the chest by two large kunai, Hidan suprises the Konoha nin by simply asking who they are.

Kakuzu soon after arrives to help, forcing Hidan's assailants to fall back. Instructing Kakuzu to leave the battle to him, Hidan exchanges blows with Asuma, eventually succeeding in obtaining some blood. After consuming the blood and drawing his symbol, Hidan links with Asuma. Not realizing what Hidan has done, Asuma charges, though falls over in pain when Hidan stabs himself in the leg. As Hidan prepares to kill Asuma by stabbing himself in the chest, Shikamaru, realizing what's going on, again immobilizes Hidan with his shadow. While Hidan is restrained, Shikamaru analyzes everything Hidan has said and done up to that point, eventually figuring out how Hidan's technique works. With that, Shikamaru forces Hidan to leave the safety of his symbol, releasing Asuma from Hidan's influence.

After Shikamaru explains Hidan's jutsu to Asuma, Asuma tests whether or not he's really free by throwing a shuriken at Hidan's ear. Finding that his ear is intact while Hidan's is left cut, Asuma decapitates Hidan, believing that to be enough to kill him. As Hidan's body slumps to the ground, Hidan curses Asuma for cutting off his head and Kakuzu for not helping him, to which Kakuzu replies that he wasn't supposed to interfere. While Asuma and the others stand shocked by Hidan's survival, Kakuzu reattaches Hidan's head to his body. As Kakuzu deals with Izumo and Kotetsu, Hidan reenters his symbol and forces his scythe into his stomach, rooting the relinked Asuma to the spot with pain. As Shikamaru rushes to Asuma's aid, Hidan stabs himself through the heart with his pike, fatally injuring Asuma.

Reinforcements from Konoha arrive as Asuma collapes on the verge of death. Although Hidan expresses interest in getting to kill them as well, the Akatsuki leader calls him and Kakuzu away. Promising to kill them later, Hidan leaves with Kakuzu to a secluded area where they spend the next week sealing the demon cat and the Three Tails. Once the sealings are over, Hidan and Kakuzu head for Konoha, eager to continue their battle. Along the way, the two are again captured by Shikamaru, the latter having been waiting for them. Although Kakuzu manages to escape from Shikamaru's shadow, Hidan is left under Shikamaru's control and is forced to fight Kakuzu.

When Kakuzu is apparently killed by Kakashi Hatake, Kakashi prepares to finish Hidan as well, but is repelled by the still living Kakuzu. Freed from Shikamaru's shadow due to its inherent time limit, Hidan charges at Kakashi while Kakuzu fires blasts of elemental attacks at the two. Needing to separate Hidan from Kakuzu if the two are to be defeated, Shikamaru volunteers to draw Hidan away by trapping him with his shadow. Hidan, having fallen for Shikamaru's technique so many times, is determined not to fall prey to it again and makes sure to avoid Shikamaru's shadow. In doing so, he doesn't pay attention to Shikamaru, allowing Shikamaru to easily punch him in the face. Trapped by Shikamaru's shadow as a result, Hidan is lead away by Shikamaru.

Upon reaching his destination, Shikamaru surrounds the area in exploding tags, preventing Hidan from escaping. Once Shikamaru's shadow recedes, Hidan attacks him, managing to get some blood in the process. After consuming the blood and drawing his symbol, Hidan stabs himself in the heart, causing Shikamaru to collapse. As Hidan begins to walk away to reunite with Kakuzu, Shikamaru tries to decapitate him, though fails to make a cut deep enough. Surprised that Shikamaru is alive, Hidan learns he has been tricked into consuming Kakuzu's blood, so he in effect destroyed another one of Kakuzu's hearts. As Hidan tries to kill Shikamaru in retaliation, he is again stopped by Shikamaru's shadow. With Hidan restrained, Shikamaru covers Hidan with the surrounding exploding tags, tying Hidan to the spot. With Hidan unable to fight back, Shikamaru activates a preprepared mark to cause the ground beneath Hidan to break away. Finally having a chance to avenge Asuma's death, Shikamaru lights a cigarette and tosses it at Hidan, causing the exploding tags to detonate. As his remains fall into the pit below, Hidan promises to kill Shikamaru in any way possible, to which Shikamaru responds by causing the pit to cave in, trapping Hidan beneath the rubble and burying him alive.

Abilities
Hidan has been gifted with immortality, presumably from his relgion, and as such he is able to survive fatal wounds and even retains the ability to speak after being decapitated. Despite this, Hidan needs to be connected to his body in order to control it. Kakuzu assists him in these instances by reattaching his limbs, allowing the wounds to heal with time. Hidan's inability to die is also used to Kakuzu's advantage, as he can attack Hidan all he wants without worrying about finding a new partner afterwards. Although the two dislike working together, this advantage makes them the ideal team. Kakuzu's partnership also served as a way for Hidan to be repaired in battle, as Kakuzu's threads could sew any part of Hidan's body back into place, allowing the wounds to heal with time.

In battle, Hidan usually wields a three-bladed scythe that he uses as a projectile while controlling it with a rope wrapped around his wrist. Although he is capable of striking even the most talented of ninja with it, Hidan claims that the scythe makes him the slowest-attacking member of Akatsuki. The three blades on his scythe are not meant to increase the damage of his attacks, but rather to increase his chances of drawing his opponent's blood. Should the scythe become inconvenient or unavailable for this purpose, Hidan can also use a retractable pike to injure the opponent.

During battle Hidan makes every attempt to acquire an opponent's blood where, upon consuming it, he draws a symbol on the ground that "links" him with his opponent. Once this link is created Hidan takes on a grim reaper-like appearance and becomes what is essentially a voodoo doll for his opponent; any damage that is done to Hidan is also done to them. Hidan first uses this ability to give himself nonfatal injuries that bring him pleasure due to the pain it causes to him and the opponent. Once he is done toying with opponents in this way he stabs himself in the heart, killing them. Links can be broken prematurely if Hidan is removed from the safety of his symbol, though it can easily be reestablished by simply reentering its borders. After Hidan uses this ability to kill Asuma Sarutobi, Shikamaru Nara faces him in an attempt to gain revenge. Hidan is unable to form a link with Shikamaru and eventually falls into one of Shikamaru's traps. With Hidan captured, Shikamaru blows him up and buries the still-speaking remains under a pile of rubble. While his actual status is currently unknown, Akatsuki no longer considers him a member.