a ghostly double or counterpart of a living person. An alter-ego.
Most likely it'll freak you out, then after you become accustomed.. it'll freak you out some more. But that's only half of what it'll do for them (as they'll be employing this other half freaking out over you)..
Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them