*sniffs* Everything I know is dead. And even though you're not here, or haven't been on in forever >.> I know this one.

They only showed four stories from the manga, basically all of them were from the first two or three books. There are ten volumes, filled with three to four stories each, sometimes. So there was a lot not in the OVA.

It wasn't necessarily an anime movie, anyway. It was just a movie. Though most of the stories have a dark or weird twist. There are a few that have a nicer ending for the people who bought the pet.

However, I've gotta say, they followed the stories they picked pretty well, in my opinion.