The concept of this one is when you go back in time and prevent your parents from meeting, then you start to disappear, but then, since you have never existed, you would've never went back in the first place to prevent your parents from meeting, thus, creating a paradox. Okay, maybe I've been watching too much Back to the Future... Thanks for viewing.
Heh, I got my boyfriend into it so we watch it a lot. :J
Cool :3