The Paptisma Is A Unused Item In Haunting Ground. The description of the paptisma reads "An alchemic item created through an intense process of refining medallions. I wonder what it does?" This suggests the way to obtain it, through the alchemical refining room, though any combination in that room is completely vain.
After the first use nothing happens, but the description of the object changes to "Mysterious item that bestow the ability the ability to read ancient text upon the player." Given that many of the game's items take their names from Latin words, Paptisma may be derived from "baptisma", which means baptism or immersion, though neither definition really fits the item's description.
Still, it's clear that originally the object was supposed to give the protagonist the ability to read certain documents. But these are not present. The item's texture is the same as the Fortis and Remedium items, the only difference being that the liquid here is green.