combination of the following:-
omni = Latin for all, entire, absolute
mesis = Hebrew term for one who takes the gaze from God
mimesis = Greek - the imitation of life through art and literature
A person interested in or willing to try any and all fetishes.
Person 1 "I don't think I can keep up with her, she's an omnifetishist."
Person 2 " oh really?"
Person 1 "Yeah, there isn't a singlefetish she won't try."