I have an INFJ friend who I think is cute but I would not say I have a crush on her.
I think it's her antics combined with the way she acts all proper when being secretly attracted to "naughty" behavior that makes her interesting. She told me about a guy she was kind of interested in and she speculated that it was because "he's a bit of a bad boy".
Who knows, if I got to know her better it might increase my interest in her. Too bad she lives on the opposite side of the planet.
One of my biggest crushes to date has been an INFJ. For a long time I thought he was an INTJ (he thought so too), but then got typed correctly. I seem to be into Ni-doms, but INFJs just top it for me, as they extrovert feeling and this just knocks me out.
I definitely have a soft spot for them, and consider them the best partner to an INTP type wise. Any specific reason for asking?