i think his character has gone through the most changes, has grown more in personality and wisdom than any other in the series. Thats what makes him so appealing :)
I think he's a fairly underrated character. He's gone through immense changes since the beginning of the series.. he started off as a 'bratty' kind of hot tempered person... then after certain events he grew to become a stronger and more solid individual. He speaks his mind and is honest.. his friend also pointed out he could accurately judge a situation which made him a good leader.
For most appealing I definitely have to say Lavi from D-Gray Man . I mean Allen and Kanda are also very appealing , but I feel like Lavi is the character that develops the most out of the three of them and he had such an unexpected backstory that made me want to see more . In fact at first I just assumed he was a constantly happy person but once I hit season four all my assumptions were proven wrong and I cried ... a lot T-T .
