Kaishakunin
The kaishaku ( Japanese 介 錯 ) or kaishakunin ( 介 錯 人 ) roughly corresponded to the “supporter” referred to in the western seconds of the seppuku , the ritualized suicide of Japanese samurai . It was incumbent on the kaishaku to behead it with a sword at the moment when the seppuku practitioner slit open his stomach.
For this, the samurai uses a long sword katana (rarely also with the older, saber-like tachi ) to separate the neck from the cervical spine (but not completely cut off) as soon as the latter has given the sign - the bowing of the head forward. Striking too early carries the risk of the gun getting stuck in a cervical vertebra and causing extreme pain. The subsequent blows required would have degraded the seppuku to a dishonorable death.
Only by abruptly separating the head from the torso ( decapitation ) is the cerebral shock caused, which causes immediate deep unconsciousness : At the time of death, the face should under no circumstances appear distorted by pain.
The kaishakunin had to carry out the blow in such a way that the head remained connected to the torso by a flap of skin and was only separated by the impact on the ground: Complete penetration would have been like the execution of a criminal and the seppuku would also have been dishonored.
The role of kaishakunin was usually assigned to a prominent, familiar, or closely related samurai. He had the most important task at this ceremony, as he was ultimately responsible for ending the seppuku with honor. After the task was incomplete, Kaishakunin often committed seppuku themselves.