Possession

Partially related to transformation stories. Typically possession happens when a ghost or demon takes control of someone else’s body. But this can happen in transformation stories where a person’s soul/mind is transferred to a different body.

In some cases the cause is that a person has died and their spirit can possess people. In other stories the person wakes up one morning to find they can take over a person’s body. What happens to their original body? Typically the body falls asleep as it is now an empty husk or perhaps it goes on with its life as if nothing has happened. Or someone else has taken Control of it.

Most of the time this occurs because of a wish gone wrong where someone wishes to be someone else. What happens to the person who is possessed? Well either their soul/personality is suppressed completely or they’re still around in their mind trying to fight back for control.

An interesting version of this story is found a lot in Japan. Where people will bonk heads and switch bodies.