Reincarnation trouble.

Reincarnation is not possession. An example can be found in the conundrum of cloning. If you make a clone from your body, what you get is only a body made compatible with your soul. If you attach your consciousness to this clone, it will be able to merge perfectly with the body, and you will be able to control the clone as if it were your original body. That is perfect possession.

The problem with this method is that the death of the clone will injure your soul. To fix this problem, some people split out a fragment of their soul, which is a very painful process, and then stuff that soul into the prepared body. This option truly solved the injury to the soul issue after the death of the clone.

But this creates another problem. This clone will later gain its consciousness and identity. It would not believe it is a mere clone anymore, and, in most cases, the clone would try to absorb the main body to become whole.