Kingdom Hearts II No darkness, no heartless?

Ok, so I heard from my friend that the reason kairi didn't have a heartless was because she couldn't form one, as she had no darkness in her heart. She formed a nobody but not a heartless.
So I was wondering, demyx is said to have no darkness inside him, does this mean he has no heartless? would that mean that by just destroying his nobody he would come back?
It would explain why his death scene is different looking.
Don't get me wrong, I'm not a crazed demyx fan looking for a way for him to come back, this is just a question I have, wondering what you guys think.

 

The only reason Kairi didnt have darkness in her heart was because she is one of the seven princesses and her nobody was made in a special case. Demyx isnt really that unique compared to namine so Im sure his somebody did have darkness in his heart and had created a heartless. And seeing how Sora defeated a lot of heartless its possible he can come back.

 

Well, your friend knows what he's talking about. The princesses of heart are the on,y ones without darkness, and they are the only people in all the worlds that can't form heartless. They can form nobodies through a complicated series of events, but that only happened at Hollow Bastion in the first game.

I don't know where you got that bit about Demyx from, but he had to have at least a bit of darkness in his heart, as everyone who's not a prinesss does.

 

When is Demyx said not to have darkness in his heart? Are you sure that's ever said?

Anyway as has been pointed out, everyone except princesses of heart has some darkness

 

Thanks, I didn't know kairi had no darkness because she was a princes of heart
And your probably right about demyx having a little darkness, I just remember xigbar saying that he couldn't fell any from him