Its an interesting series. A topic that hasn't been touched by any other anime (as far as I know, if there is one then do let me know ^^) A world without death and the only escape is through living life at its fullest and enjoying every moment of it.
@6pack: (ignore if you already know) Watch the final episode till the end after the ED. It has a prologue. My friend missed it since he assumed it ended then and there. Idiot then deleted it and re-downloaded it when I told him about it.