My ISFJ kindred spirit friend calls me on my "bullshit" all the time.
I'd say something like 'I have no feelings for that person.' She would say, "Yes, you do. Shut up."
Me: *deep deep inside agrees, big mischievous smile reveals itself* Okay, you got me.
If it's personal, I keep my 'Fi' pretty tightly locked up, but my XSFJ friends can tell. My ISTJ can't, don't know how to sympathize or anything so she accepts what I say about my 'emotions'.
It's like this...I 'say' a lot of things but I don't always mean them. Sometimes I'd say something to poke at the waters, to poke at you, but I don't mean it. The other person will impress me greatly if they know me enough that they can sort through all the 'information' that I am teasing them with.
I do this thing ... where the other person would say something really obvious and I don't respond (could be because I have no response or it's uninteresting) so they continue to explain it. And once they do that, I'd pretend I don't get the idea/word/concept so I will give them this confused, furrowed brows look...and hahahaha...they will go on and on for fifteen minutes trying to explain this very simple idea/word/concept to me. I find it funny, no idea why. It works every time. I don't think anyone gets this joke; it's this weird thing of mine. Sometimes I just like giving people a confused look even though I understand them perfectly and what they are saying is extremely simple. I just want to see what they would say, I think. I sort of push them into a sort of rant and they get confused, like, why isn't she getting this? what am I doing wrong?
I only do that to close friends.
I like tirade sometimes. I am also hugely sarcastic so if you can't tell, yikes... I have met sarcastic people who I can't tell are being sarcastic so it's a sort of natural communication thing. Some people gets it immediately, some can't see it from a mile away.
I like to toss out things and see what kind of reactions I get back from people I am very close to, to see what I can fish out of them and out of myself. I like to mentally play, you see.