In the days of Samurai, seppuku was a sort of death penalty for not following the ways of the Samurai or for committing treason. The person in question would slice their sword down their chest and to the left and right in the shape of an upside-down "T". If they were able to complete this task and have all their guts spilled out, then the Samurai was absolved of his crime and he was honored in death. At least, that's how I understand it.
