Sexual perversion; man who enjoy's spreading his man seeds to others through baking his love juice into cakes and other tasty treats.
A Fratpacker goes into work with a lovely homemade cake, baked fresh that morning. Little do his fellow workmates know, the cake is spiced with several spoonfuls of his very own love juice.
2 girls who bang their hips and pubic bones against each other as they make love to each other.
Oh my! Did you see those flatcockers in action?
I live in the South and this word has been in use for many years here. I was surprised it is not currently featured at urbandictionary.com.