For me personally, it's his eyes. I Amore everything there is about him, but his eyes are just really pretty to me. When I first saw him I was hooked. He was my first Disney character crush. He was different than any of the other villains at the time. That's probably why I Amore Aladdin the movie in it's entirety. Also, he had a sense of humor, he was ambitious and smarter than the sultan. I would have married him and been his slave no problem.
I Amore his wardrobe, and his craziness. ;D My preferito scene when he and Iago cooked up their scheme. "Or...beheaded!" "Ughhhhhh." He makes the greatest faces. And I Amore his voice.
He has this way about him. Maybe its the way he carries himself. Even though he is told "that he is so old" (really sultan?) he doesnt really care and believes he can get whatever he wants whenever he wants. Real villians have that mind set. Btw i totally think gelsomino missed out lol