Guess that anime

No.13354041 ViewReplyOriginalReport
having trouble finding out the name to a series I watched a while back on dvd.

-the animation seemed pretty recent by the way it looked.
-Start of the series is like a harem anime with two girls fightan over this one guy by he suddenly and inexplicably gets pulled into a portal and everything gets dark and crows are trying to eat him or something.
-Nearly every episode started on a play stage and had some female character talking about how sad they were that apparently everyone died
-everyone dying is confirmed after awhile and the protagonist eventually finds out he's in a computer program after the cities got destroyed or something and the series ends with him follow some footsteps in an apocalyptic wasteland.