@yockeypuck
Demons are incapable of repentance because they exist as spirits in a realm that transcends time. Their choice to reject God in the spirit realm is irrevocable and eternal, and they know that before making it. Such an understanding of evil entities is in no way contrary to Christian repentance and forgiveness, as they are a different kind of being from humans that exist in a different manner, where the concept of repentance doesn't really apply. Orcs as fallen and corrupted entities are similar to this.