Charlie is an individual who resides within the Los Angeles Dollhouse after mass wipes destroyed the world-at-large. Charlie tattooed Priya Tsetsang's birthmark on her lower back so that her actual identity will always be known, should be ever be wiped. (S1: "Epitaph One")
Charlie did not appear onscreen and was only mentioned in dialogue in "Epitaph One", making him an unseen character. It was also not revealed whether or not Charlie was the persons actual name (thereby making him an original personality/actual) or if this was the identification of a former active with no other identity. In the NATO phonetic alphabet, which the Los Angeles Dollhouse uses to name their actives, "Charlie" is used for "C"