Noroi Kubi Bukuro

The Accursed Head Bag was created by the then-newfound Dark Oracle of Void Tonbo Toryu, and gifted to a shugenja-ko who had traveled to ask how could she keep her enemies from ever harming her again. She fashioned multiple copies, each one stealing a portion of her own soul, sacrificing her own reincarnation in order to deny her enemies the same.

Abilities
The bag had a tiny web-work of black lace inside, and it was preserved the removed head of a downed enemy. This trapped his soul as well, the spirit was denied reincarnation and could not even Ningen-do to journey into the afterlife. If the bag was opened, the trapped soul would immediately escape, and the head would begin to decay normally.