There are thousands of dimensions beyond ours, and between them is the Void.

For the many years that it spent isolated and unnoticed, it posed no threat at all. It wasn't until people started breaking down those formally-unbreakable walls between their world and others that it began to see human minds as a viable food source, and started growing.

The IDPF (Inter-Dimensional Police Force) works to combat the Void by arresting the illegal dimension crossers that feed it and restoring a natural balance to the worlds that they've altered.