The fact people are suggesting Sephiroth more than Cait Sith is disturbing and wrong.

Remove Sephiroth and you remove most of the game, as well as your main character's character. Probably destroy Aerith's character, too.

Cait Sith is literally the guy who just says Imma join your party and you can't stop him. Then five minutes later at Gungaga your party is like "there's a traitor among us. But WHO?!"

I smurfing wonder.