None of the misteries pay off, none of the answers are satisfactory, the main mystery of what happened to Ayumi is just plain stupid and none of the characters have much depth.
The author tries to include heavy elements like GOD, and WAR and GENOCIDE into the mix, but its obvious he bit more than he could chew, none of them have any gravitas or payoff, and the story ends up being the kind were the entire problem could be avoided with a single sentence at the beginning.
There are better comedy romances out there, its not the worst, give it a go on a lazy sunday, but its definitely not the best by a LONG shot.