Ali is likeable in that he's completely unlikeable. Compare that with Nena, where people really liked her cute-but-clearly-nuts demeanor until she did something REALLY psycho. Ali is a bad guy through and through, and he's loud and proud about it as well.
It was even better when the Japanese version was airing, one episode a week. We had more time to be like "Aww, she's like a crazier, hotter Flay!" before going "SHE MUST DIE!"