It seems that whenever ENFPs start getting serious around you, bringing out their depth, is when they are opening up to you. ENFPs are very playful, but for me, it's not to hard to know when they're for real.
Is it that by its indefiniteness it shadows forth the heartless voids and immensities of the universe, and thus stabs us from behind with the thought of annihilation, when beholding the white depths of the milky way?
For me, THey make alot of warm physical contact. They'll do alot of "playing around" so to speak. They'll do cute little touching, whether that means alittle shove, slap, touching of the ear, rubbing your back etc.. They'll also play cute little "tricks" on you and smile while doing it. Heck, they usually smile at everything when their interested in something. LIke for instance: I like to wear a hat and just about every enfp I have met, will steal it and hide it in the most obvious place. They do this, so your encouraged to "Play with" and show just as much warmth in their direction.. Tricky little buuugars they are.. lolz though the smileing kind of gives away..
"People often Find out the truth, when its too late!!!"