I dunno. He's hardly been seen, and when he is its a flashback from his younger brother about Itachi destroying their whole clan just to see how strong he was but leaving Sasuke alive. And Itachi isn't a loner, and doesn't have the gruff, leave me alone kinda additude either. I've just always wondered. I now why they like his brother..Cause of the loner part, and additude, and wanting to kill him..just never understood why Itachi.
Abumi Zaku