9. Ghosts
Maybe we linger on Earth, choosing to stay here, where we feel safe; there is no light to go into. Some spirits may stay where they felt at peace; I've heard the ghosts of Marilyn Monroe and Montgomery Cliff haunt the Roosevelt Hotel in Hollywood. Maybe people, who die unexpectedly, stay because they don't realize they're dead. Some may want to live out their greatest moments again, or are too scared to move on - the Hogwarts' ghosts in Harry Potter! More may stay to look after and watch out for their loved ones, to guide them through their lives on earth. (These are spirit guides, loved ones who've died and chosen to come back to guide us, as opposed to our guardian angels, who've never been human, are a common belief for many - part of the whole re-incarnation cycle - see #8.) This one isn't the most logical, since if everyone who dies stayed, there would be more ghosts than humans and there should/would have been a lot more ghostly sightings!