They say the human body's skin cells completely replace themselves once every seven years or so. This means that by the end of this time frame, you are essentially a completely new you. For me, this means that if I slept with you seven years or longer ago, the shit never happened. My vagina has been completely renovated, and there is no longer any trace of you or the seven minutes of sex we may have had. I am so serious about this rule that I am pretty sure I could pass a lie detector test if questioned.
So, that questionable encounter from the 90s? Gone. That ex you wish you'd never met in the first place? History. That wild weekend in Vegas? Non-existent. As long as it was 2006 or prior.