Ghost Girlfriend

You just moved into a surprisingly-inexpensive house. After doing some digging into the history of the property, you discovered the former tenant disappeared under "mysterious circumstances". A few nights later, strange things start happening: the telephone ringing constantly with no-one on the other end, the TV turning on by itself, and furnature being out of place. Reluctantly, you come to the conclusion that your new home might very well be haunted. But is this paranormal entity a friend or foe?