1. She has
feet fetish. :D :(
Well, actually, it sounds odd at first glance given that the common phrase is "foot fetish". It's not common for 'feet' a plural noun to functions as an adjective, but it could be considered OK if 'feet fetish' refers to a fetish for different kinds of feet, say, non-human feet.
But in that case, and since 'fetish' is a count noun, either 'a' or -s should be added,
EX: She has a feet fetish. (fetish for all kinds of feet)
EX: She has feet fetishes. (various kinds of fetishes for all kinds of feet)
But, again, 'feet fetish' is not the common form. It's a made up phrase.