Jashin cult

(ジャシン; Literally meaning "wicked heart; evil design") is the god worshiped in Jashinism (ジャシン教, Jashinkyō). One of its followers is the Akatsuki member Hidan. Jashin, according to Hidan, expects that all followers of Jashin - so named "Jashinists" - bring nothing less than utter destruction and death. Hidan always used to pray to Jashin before a fight, asking for a "good kill." If he is unsuccessful, or is not allowed to kill, he prays for forgiveness.

When undergoing a sacrifice, Hidan changes appearance after ingesting his opponent's blood. His skin then turns black with white markings representing a skeleton, a symbol of absolute death. He draws Jashin's symbol on the ground in his own blood and stands in the center. This symbol is an equilateral circumscribed triangle (an upside down triangle with a circle around it). Once his sacrificial ritual takes place, any kind of pain or injury that Hidan inflicts upon himself receives is also inflicted upon his sacrifice, be it a mere scratch or a pierce in the heart. However, this ritual can be broken if Hidan either steps or is forced out of the circle. This technique is called "Curse Technique: Death Controlling Possessed Blood."

Hidan is the "successful experiment of the Jashin religion's secret jutsu", which makes him become immortal. He uses this advantage to otherwise fatally injure himself while he is linked to his opponent in order to kill them.

This technique is Hidan's primary method of killing his opponents in the way of the Jashin religion.

First, Hidan makes every effort to draw blood from his opponent and consume it. After that, his skin turns black with white markings representing a skeleton, a symbol of absolute death. He then draws Jashin's symbol on the ground in blood and stands in the center. This serves as the link between him and his victim.

Once his sacrificial ritual takes place, the victim is linked with Hidan until he either steps or is forced out of the circle. Any kind of injury that Hidan inflicts upon himself (or the injury they inflicted on him) is inflicted upon his target, be it a mere scratch to a pierce in the heart. If Hidan is forced to step out of the circle, the link is broken and the victim is set free, but all Hidan has to do is to step back into the circle to reactivate the link. Basically, this technique makes Hidan a living voodoo doll.

Hidan's immortality is due to the "successful experiment of the Jashin religion's secret jutsu", so he can fatally torture his opponents in any way he desires without killing himself, and he clearly enjoys the pain on himself as well. However, he does indeed complain that it hurts like one normally does in pain, after he finished off Asuma.