Seppuku

Seppuku or known as "hara-kiri", is a form of Japanese ritual suicide by disembowelment.
Originally, it is only used by the samurai as it is a key part of samurai bushido honor code; it was used by samurais to die with honour rather than being capture and disgrace in battles. Samurai also could use seppuku if it is under their daimyo's(feudal lord) order to commit, or performed for other reasons that had brought shame to them. The ceremonial disembowelment, which is usually part of a more elaborate ritual and performed in front of spectators, consists of plunging a short blade, traditionally a tantō, into the abdomen and moving the blade from left to right in a slicing motion.

The ceremony

A samurai was bathed, dressed in white robes, fed his favorite meal, and when he was finished, his instrument was placed on his plate. Dressed ceremonially, with his sword placed in front of him and sometimes seated on special cloths, the warrior would prepare for death by writing a death poem. With his selected attendant (kaishakunin, his second) standing by, he would open his kimono (clothing), take up his tantō (knife) and plunge it into his abdomen, making a left-to-right cut. The kaishakunin would then perform daki-kubi, a cut in which the warrior was all but decapitated (a slight band of flesh is left attaching the head to the body).