Vak Jugglers (バクジャグラー) are monsters in The World R:2 that are created when swords that were left behind on the battlefield are possessed by the souls of dead soldiers. Since they were first inanimate objects, some scholars believe that they should not be considered as a monster.
It is believed that the dead souls do not realize that they are dead, and will stay on this earth until the swords they possessed are broken. It is also said that it will suck the souls of those who have been struck down by its blade. Because of this, even seasoned adventurers hesitate to fight this monster.