You gotta admit, regardless of which anime you watch, Ulquiorra was f'n badass. *spoiler for those of you who have not yet enjoyed life and watched/read Bleach* Not only was he the only Arrancar to have two release stages, he's the only one to manage to kill Ichigo. Not just once, but TWICE. And both times they were epic.
Not to mention the fact that he managed to steal Orihime's heart. If he made it through the Aizen Arc. . . could you imagine how great they would be together? I mean, Orihime always had the hots for Ichigo, still does, but the moment he started to show signs of his inner hollow she was horrified, even paralyzed. But with Ulquiorra, she showed no fear, she was pulled towards him. And that moment she reaches out to him as he's vanishing. . . you know he had her heart. So not only does he kill Ichigo, he also steals his girl. HOLY DAMN this guy is legit.