Maybe he thought it was this manga that this series was based on:
http://www.mangaupdates.com/series.html?id=13106
It deals with the same thing. Would have liked that were true though it's quite good it deals with alot of aspects when it comes to humanity when there's a disaster both the good and bad... don't think that this series though will go to deeply into that bad aspect of humanity unless there willing to do scenes of rape and people getting killed/murdered/suicide.