[@ArkmageddonCat]
http://en.wikipedia.org/wiki/Red_string_of_fate

Beside the wika definition, in a summarized form to the best of my ability: The Red String of Fate is connected to everyone, generally being in pairs and is connected to their pinkies. These strings may be far and wide but those two individuals who are  tied together by these strings will definitely meet up. Generally used to represent marriage, you can twist this power due to your character's back-story to locating 'Supernaturals' and after you find them these strings between you and your captured victim will sever. (Or some way in that, i dunno xD)