He appears to be somewhat god-like, so I'd have to say his power is the main thing that makes him likeable. Also, there was a period in the game when most kids looked up to him, such as Cloud, but also because of his enchanting beauty. In all of the scenes he seemed to make this eerie atmosphere, with the dark music, and pulsing, and his insanity, you couldn't even seem to compromise, or speak with him, because he didn't ever care to listen. He had motivation for what he did and because of it, he was in his own little world.