Yes I believe Aerith is the way it was meant to be spelled. but it is supposed to be pronounced Aeris, because that's how it is pronounced in japanese. I used to talk this asian kid and talk about FF7 with him, he would constantly pronounce "Sephiroth" as "Sephiros"
So I guess that means in English if you pronounce Sephiroth the way it is spelled, you may as well pronounce Aerith the way it is spelled.
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