Cicero... The moment he came into the game I got a "Kefka-ish" feeling about him. I'm sure anyone who had played FFVI would have felt that way. I let him live anyway.
Hey if you don't kill him you can still get his outfit. It will be on a desk at that place after letting him live and saying a lie to Astrid. That's how it is in mine... but I don't see him anywhere...