I'm pretty sure my best FWB was an ISTP. He certainly confused the shit out of me. In the best way possible. It almost seemed like he didn't realize he had feelings Or something like that. Like, he'd say sweet things to me, and not realize that he's being sweet...? I have no idea how to explain it.
I'll never forget this exchange in particular:
ISTP: "You know, you can text me more. I wouldn't mind."
Me: "Really? I told you I didn't mind keeping this a super-casual thing, yeah?"
ISTP: *pokes me in the belly and smiles big ISTP sexy smile* "Yeah, so,
super-casually text me more, for fuck's sake."
Oh god I miss him.