Whew, this is another sucky one!
I think Daemon Spade is one of the more interesting characters in the series. He's a very dynamic character. Daemon has a really nice, fleshed-out background story. His reasoning for the things he did is reasonable considering his past.
He started out loving the Vongola family. He wanted it to be strong and powerful. His lover, Elena, also shared his passion for Vongola. He felt betrayed by Primo because he was "soft" which lead to Elena's death. So he wanted to make the Vongola family strong. He was even the Mist Guardian for the second generation of the Vongola family.
The fact that he caused all these problems just to get revenge and make the Vongola he and Elena loved stronger, I have to admit, takes a lot of dedication. It really shows us how much he loves Elena if he was willing to go through all that just because she died.
I really liked his character development. At the end when Tsuna defeated him, he, in a way, redeemed himself by asking for Elena's forgiveness for what he had done to the Vongola that she loved. Not only that, he accepted Tsuna as his family. He knew Tsuna was lying about his Hyper Intuition, but he still went along with it.
Because of his redemption, I love him and have so much respect for him. Yeah, the things he did were terrible. I won't dismiss that. But the process he went through to realize that he was wrong and that it was his time to go was just amazing. It's one of the better KHR arcs. And definitely one of the more touching stories.
I wish Daemon stuck around a little longer. He's just really interesting.
Sorry that sucked, Chris!