Well, it changed depending on the fmv, didn't it? I mean there was one scene in FFVII(after the highwind was nearly bowled over by Ultimate Weapon and Tifa fell to the deck) where it looked like she was being attacked by her boobs and that they had seized the opportunity to take over.
In Advent Children she resembled a human being and I'd like to think that the CG render that Andro provided looks exactly like her.
-Sin
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