The [[Vessel of Sin|Vessel of Wrath]], inhabited by the demon [spoilers][[Seth Twiright]][/spoilers]. 

A magical tool created by the [[Seth Twiright]] in shape of a golden key. Capable of shapeshift, it can fit any lock and take the form of several weapons, like a dagger, a sword or a bullet. Wielded by several individuals across the ages, eventually it fell in possession of [[Nemesis Sudou]], who used it as the ultimate weapon for fullfil her goals.
grim the end