You'll never see my emotions in their most primal or even sincere stage if I have anything to do with it and it almost always manifests negatively. If I express myself when I'm not out of control, I never begin anything with "I feel" and it always has an impersonal feel to them. I use similes, metaphors, sarcasm, allusions etc. to get my point across. For example, if I was describing an irresponsible urge, I'd say "I'm like Mathieu (from a Sartre novel) and I despise that much as I despise him!" (and yes, I expect you to know what I'm talking about) And I run the risk of extrapolating my emotional state into some sort of philosophical discourse.
My most negative outbursts of Fi (now the shadow Fe, I suppose, now that it's out in the public) are long, passionate even exaggerated rants, and if it's directed at someone in my vicinity, I'd attack them rather viciously with words. If they're not around, I grab hold of my best friend and verbally rip the object of my frustration to shreds (and I can be rather clever with words), and if someone pisses me off that much, it's likely that I'd not be able to refrain from deriding him to my friend at every opportunity even after my rage has passed. If I'm just emotionally charged, I'd threaten and boast about outrageous things, for example, threaten to drink myself into oblivion and destroy the hotel room I'm in, or leave someone forever (it was my parents for the longest time) and do hedonistic shit.
So no, Fi doesn't "look like" anything in my case because you'd never see it. It is very developed though, and I have a strong sense of empathy and compassion that just don't show. Most people are surprised to learn I have these feelings, actually. An INTP friend told recently my Fi outbursts are quite frightening, and I admitted immediately afterwards I was boasting (it was the drinking thing; I never liked the taste of alcohol and have never finished one beer. In fact, I'm always ridiculously self-disciplined). He knew I was being melodramatic, but apparently it still unnerved him. There are melodramatic threats that don't scare anyone, and there are my threats.