It means like the person that someone has on the side not including his or her girlfriend or boyfriend.
I text my friend really late at night. Just to see what was going on. Her boyfriend then asked if I was her "Side Meat".
Cykliczny mail ze słowem dnia
Maile są wysyłane z adresu firstname.lastname@example.org. Obiecujemy, że nie będziemy wysyłać żadnego spamu.