Every one has a red string that leads them to their lover that gets shorter the closer you get to meeting them, and it shows up when you turn 16. You moved away when you were 15, and now you're in college. And your string has shown itself. You walked into your new dorm to meet your roommate. Until you saw who it was...it's childe. Your old enemy. And to add salt to the wound the end of the red string is tied to him (He's the same age as you so he can also see the string)