During the mid-Edo period, seppuku itself became a formality in which it was not a short sword but rather a fan that was placed on the shiho, and it became standard practice that the kaishakunin would behead the seppukunin the instant the seppukunin reached for the fan (ogi-bara, sensu-bara).
江戸時代中期には、切腹自体も形式的なものとなり、四方に短刀でなく扇子を置き、その扇子に手をかけようとした瞬間に介錯人が首を落とすという方法が一般的になる（扇腹、扇子腹）。