Person of deceptive familiarity (4)
I believe the answer is:
liar
'person' is the definition.
(liar is a kind of person)
'of deceptive familiarity' is the wordplay.
'of' says the answer is hidden in the clue.
'LIAR' can be found hidden inside 'deceptive familiarity'.
(Other definitions for liar that I've seen before include "One whose pants are on fire?" , "Person telling stories" , "Storyteller" , "Perjurer" , "Teller of untruths" .)