Bartholomaios, formally known as Duo Iqus, is a "Killing Doll" like Tres Iqus. His designation is HC-IIX. He is Tres' "brother" as both were part of the ten "HC Series" (homo caedelius) made by Professor Gepetto Garibaldi. Unlike Tres, Bartholomaios' body parts have been replaced several times over the years, resulting in the complete loss of his combat memory in the process. He is now a member of the Department of Inquisition, through which he is referred to as Brother Bartholomaios.