The concept of Purgatory is intricately tied to the concept of what is required for forgiveness. Many Christians would, I believe, agree that for sins to be forgiven they must be recognized and repented. If you screwed up, you must realize that you really did screw up and be sorry you did so before you can be forgiven.
This is covered in many non-RC churches during the confession. The Creedal Christian Community says that you can be sorry for things you have done without knowledge and be forgiven them directly. You simply need to be aware that you have done things, even if unwittingly, that has caused harm to others.
The concept of Puragtory is directed towards the person who has committed sins and dies without either recognizing he has sinned or while recognizing the fact, has not repented.
In that situation the Roman Catholic Church provides the spiritual equavalent of a halfway house, a place where the person has the opportunity for appeal and redress, where they can examine their life and repent for those things that have gone unrepentant.
Aslan is not a Tame Lion