Most original and unique series

I'm not sure about original but I find Mirai Nikki unique, I Liebe the story and I Liebe how the plot goes. I find it fascinating how their diaires can tell the future

Original??? I don't really know, but i think It's deffiently unigue :D

XXXHolic, it has such different art then most animes, and it does have a bit of a mystery to it :)