When you tell your girlfriend that you need to talk she has mixed feelings. You ask her if she would be okay with paying your debt with her body as you have lost a bet to your friend. She can't believe that you prefer for her to be used by your friend instead of just paying him the money, but she finally agrees because she loves you. When the friend comes by, she is still a bit hesitant. She says she will do it if you watch. She starts playing with his cock and realises that it is way bigger and way better than yours. She continues to enjoy herself more and more lettig him use her ass and switching between ATM. She makes fun of you and your insufficient cock and states that she may wanna do it with your friend more often. He cums in her ass and she teases you about tasting it if you're good. From now on she is your slutty GF and you are a cuck.