...Boring. I can't really do anything but sleep or think when I'm not using someone else's body. I can't touch anything physical, or even hear or see things.

But there's enough entertaining things when I do have a body to mess around in to make it worth it. You wouldn't understand most of it. Not that it's difficult; but the thing that makes it interesting comes from three thousand years of being bored enough to find anything new interesting. Someone as young as you can't comprehend that level of boredom.